From 4f9deeb57adcc71c9b937afb0bf9425c6f93285a Mon Sep 17 00:00:00 2001
From: indigo <indigoo@gmail.com>
Date: Sat, 18 Jul 2026 04:03:58 +0800
Subject: [PATCH] Phase 4: Architecture & tooling investment

Fixes a real N+1 API-call bug (per-cell project-member fetches in shot/asset
task-status cells, now a shared cached store), replaces a polling-based
in-flight request de-dup with promise memoization, adds markRaw() around
icon components in reactive state, and fixes a deep watcher that re-scanned
the whole projects array just to trigger thumbnail loading.

Introduces useAsyncAction and usePermission composables to cut duplicated
store boilerplate and duplicated role/admin checks, applied only where the
existing code was a clean match rather than forced onto everything. Extracts
assets.ts's shared per-asset optimistic-update/rollback helper without
merging the single and bulk API paths, which hit genuinely different
endpoints. Adds toast-on-error for previously-silent secondary loads and
fixes a dead try/catch in the router's auth-init guard along the way.

Also fixes a thumbnail-loading regression introduced earlier in this same
pass: the new ID-keyed watcher never fired on a repeat visit to the Projects
page when the store already held the same project list, so thumbnails
(local component state, reset per mount) silently stopped loading after the
first visit. Replaced the watcher with a direct call after each fetch.

Table virtualization, splitting the two largest view files, broad store
caching, and moving domain types into types/ were scoped out as separate,
higher-risk follow-ups (documented in frontend_tasks.md).

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
---
 .../components/asset/EditableTaskStatus.vue   |  22 ++-
 .../components/episode/EpisodeDropdown.vue    |  10 +-
 frontend/src/components/layout/AppSidebar.vue |   4 +-
 .../src/components/layout/ProjectSwitcher.vue |   7 +-
 .../project/TechnicalSpecsManager.vue         |  10 +-
 .../project/TechnicalSpecsPanel.vue           |  10 +-
 .../components/shot/EditableTaskStatus.vue    |  24 +--
 frontend/src/components/shot/ShotBrowser.vue  |  28 +++-
 .../src/components/shot/ShotDetailPanel.vue   |  22 +--
 .../src/components/task/TaskDetailPanel.vue   |   7 +-
 frontend/src/components/task/TaskList.vue     |   8 +-
 frontend/src/composables/useAsyncAction.ts    |  41 +++++
 frontend/src/composables/usePermission.ts     |  19 +++
 frontend/src/router/index.ts                  |  16 +-
 frontend/src/stores/assets.ts                 | 141 ++++++++----------
 frontend/src/stores/auth.ts                   |  33 +---
 frontend/src/stores/episodes.ts               |  85 +++--------
 frontend/src/stores/projectMembers.ts         |  80 ++++++++++
 frontend/src/stores/projects.ts               |  77 +++-------
 frontend/src/stores/settings.ts               |  72 ++-------
 frontend/src/stores/taskStatuses.ts           |  69 ++++-----
 frontend/src/stores/tasks.ts                  |  34 ++---
 frontend/src/views/EpisodesView.vue           |  14 +-
 frontend/src/views/ProjectSettingsView.vue    |   7 +-
 frontend/src/views/ProjectsView.vue           |  24 ++-
 frontend_tasks.md                             |  81 +++++-----
 26 files changed, 453 insertions(+), 492 deletions(-)
 create mode 100644 frontend/src/composables/useAsyncAction.ts
 create mode 100644 frontend/src/composables/usePermission.ts
 create mode 100644 frontend/src/stores/projectMembers.ts

diff --git a/frontend/src/components/asset/EditableTaskStatus.vue b/frontend/src/components/asset/EditableTaskStatus.vue
index 859db53..18ba4f6 100644
--- a/frontend/src/components/asset/EditableTaskStatus.vue
+++ b/frontend/src/components/asset/EditableTaskStatus.vue
@@ -169,8 +169,9 @@ import { User, Search, Check, X } from 'lucide-vue-next'
 import TaskStatusBadge from '@/components/task/TaskStatusBadge.vue'
 import { TaskStatus } from '@/services/asset'
 import { taskService } from '@/services/task'
-import { projectService, type ProjectMember } from '@/services/project'
+import type { ProjectMember } from '@/services/project'
 import { useTaskStatusesStore } from '@/stores/taskStatuses'
+import { useProjectMembersStore } from '@/stores/projectMembers'
 import type { CustomTaskStatus, SystemTaskStatus } from '@/services/customTaskStatus'
 import { useAvatarUrl } from '@/composables/useAvatarUrl'
 
@@ -202,11 +203,12 @@ const { getAvatarUrl } = useAvatarUrl()
 
 // Use the shared task statuses store instead of direct API calls
 const taskStatusesStore = useTaskStatusesStore()
+const projectMembersStore = useProjectMembersStore()
 
 const isUpdating = ref(false)
 const isAssigning = ref(false)
-const isLoadingMembers = ref(false)
-const projectMembers = ref<ProjectMember[]>([])
+const projectMembers = computed<ProjectMember[]>(() => projectMembersStore.getMembers(props.projectId) || [])
+const isLoadingMembers = computed(() => projectMembersStore.isLoading(props.projectId))
 const searchQuery = ref('')
 
 // Filtered project members based on search query
@@ -306,17 +308,12 @@ const fetchStatuses = async () => {
   }
 }
 
-// Load project members
+// Load project members (shared cache across all EditableTaskStatus instances for this project)
 const loadProjectMembers = async () => {
-  if (projectMembers.value.length > 0) return // Already loaded
-
-  isLoadingMembers.value = true
   try {
-    projectMembers.value = await projectService.getProjectMembers(props.projectId)
+    await projectMembersStore.fetchProjectMembers(props.projectId)
   } catch (error) {
     console.error('Failed to load project members:', error)
-  } finally {
-    isLoadingMembers.value = false
   }
 }
 
@@ -400,10 +397,9 @@ onMounted(() => {
   loadProjectMembers()
 })
 
-// Refetch statuses when projectId changes
+// Refetch statuses and members when projectId changes
 watch(() => props.projectId, () => {
   fetchStatuses()
-  // Clear project members when project changes
-  projectMembers.value = []
+  loadProjectMembers()
 })
 </script>
\ No newline at end of file
diff --git a/frontend/src/components/episode/EpisodeDropdown.vue b/frontend/src/components/episode/EpisodeDropdown.vue
index 441b6fc..be9b639 100644
--- a/frontend/src/components/episode/EpisodeDropdown.vue
+++ b/frontend/src/components/episode/EpisodeDropdown.vue
@@ -83,7 +83,7 @@ import {
 } from '@/components/ui/select'
 import { Button } from '@/components/ui/button'
 import { Label } from '@/components/ui/label'
-import { useAuthStore } from '@/stores/auth'
+import { usePermission } from '@/composables/usePermission'
 import { episodeService, type Episode } from '@/services/episode'
 
 interface Props {
@@ -100,7 +100,7 @@ const props = defineProps<Props>()
 const emit = defineEmits<Emits>()
 
 const router = useRouter()
-const authStore = useAuthStore()
+const { isCoordinatorOrAdmin } = usePermission()
 
 // Reactive state
 const episodes = ref<Episode[]>([])
@@ -108,11 +108,7 @@ const isLoading = ref(false)
 const error = ref<string | null>(null)
 
 // Computed properties
-const canCreateEpisodes = computed(() => {
-  const userRole = authStore.userRole
-  const isAdmin = authStore.user?.is_admin
-  return userRole === 'coordinator' || isAdmin
-})
+const canCreateEpisodes = computed(() => isCoordinatorOrAdmin.value)
 
 const sortedEpisodes = computed(() => {
   return [...episodes.value].sort((a, b) => {
diff --git a/frontend/src/components/layout/AppSidebar.vue b/frontend/src/components/layout/AppSidebar.vue
index 803abb4..c0dbd36 100644
--- a/frontend/src/components/layout/AppSidebar.vue
+++ b/frontend/src/components/layout/AppSidebar.vue
@@ -123,10 +123,12 @@ import {
 } from 'lucide-vue-next'
 
 import { useAuthStore } from '@/stores/auth'
+import { usePermission } from '@/composables/usePermission'
 import ProjectSwitcher from './ProjectSwitcher.vue'
 import UserMenu from './UserMenu.vue'
 import SidebarColumnSwitch from '@/components/ui/sidebar/SidebarColumnSwitch.vue'
 const authStore = useAuthStore()
+const { isCoordinatorOrAdmin } = usePermission()
 const { state } = useSidebar()
 const route = useRoute()
 const user = computed(() => authStore.user)
@@ -150,7 +152,7 @@ const navigationItems = computed(() => {
     { title: 'My Tasks', url: '/tasks', icon: CheckSquare },
   ]
 
-  if (userRole.value === 'coordinator' || authStore.isAdmin) {
+  if (isCoordinatorOrAdmin.value) {
     baseItems.push(
       { title: 'Projects', url: '/projects', icon: FolderOpen },
       { title: 'Team', url: '/users', icon: Users }
diff --git a/frontend/src/components/layout/ProjectSwitcher.vue b/frontend/src/components/layout/ProjectSwitcher.vue
index 0f198bd..af9f0dd 100644
--- a/frontend/src/components/layout/ProjectSwitcher.vue
+++ b/frontend/src/components/layout/ProjectSwitcher.vue
@@ -135,11 +135,13 @@ import {
 } from "@/components/ui/sidebar";
 import { useAuthStore } from "@/stores/auth";
 import { useProjectsStore } from "@/stores/projects";
+import { usePermission } from "@/composables/usePermission";
 
 const router = useRouter();
 const { isMobile } = useSidebar();
 const authStore = useAuthStore();
 const projectsStore = useProjectsStore();
+const { isCoordinatorOrAdmin } = usePermission();
 
 // Get projects and active project from store
 const projects = computed(() => projectsStore.availableProjects);
@@ -148,10 +150,7 @@ const isLoading = computed(() => projectsStore.isLoading);
 const error = computed(() => projectsStore.error);
 
 // Check if user can create projects
-const canCreateProjects = computed(() => {
-  const user = authStore.user;
-  return user?.is_admin || user?.role === "coordinator";
-});
+const canCreateProjects = computed(() => isCoordinatorOrAdmin.value);
 
 const setActiveProject = (project: any) => {
   projectsStore.setActiveProject(project);
diff --git a/frontend/src/components/project/TechnicalSpecsManager.vue b/frontend/src/components/project/TechnicalSpecsManager.vue
index 7927625..2067c38 100644
--- a/frontend/src/components/project/TechnicalSpecsManager.vue
+++ b/frontend/src/components/project/TechnicalSpecsManager.vue
@@ -83,7 +83,7 @@ import { ref, computed, onMounted } from 'vue'
 import { Edit, AlertCircle, RefreshCw, Bell, X } from 'lucide-vue-next'
 import { Button } from '@/components/ui/button'
 import { Card } from '@/components/ui/card'
-import { useAuthStore } from '@/stores/auth'
+import { usePermission } from '@/composables/usePermission'
 import { useToast } from '@/components/ui/toast/use-toast'
 import { projectService, type ProjectTechnicalSpecs } from '@/services/project'
 import { notificationService } from '@/services/notifications'
@@ -97,7 +97,7 @@ interface Props {
 
 const props = defineProps<Props>()
 
-const authStore = useAuthStore()
+const { isCoordinatorOrAdmin } = usePermission()
 const { toast } = useToast()
 
 // State
@@ -108,11 +108,7 @@ const isEditing = ref(false)
 const showNotification = ref(false)
 
 // Computed properties
-const canEdit = computed(() => {
-  const userRole = authStore.userRole
-  const isAdmin = authStore.user?.is_admin
-  return userRole === 'coordinator' || isAdmin
-})
+const canEdit = computed(() => isCoordinatorOrAdmin.value)
 
 // Methods
 const loadSpecs = async () => {
diff --git a/frontend/src/components/project/TechnicalSpecsPanel.vue b/frontend/src/components/project/TechnicalSpecsPanel.vue
index 54ebab2..199028d 100644
--- a/frontend/src/components/project/TechnicalSpecsPanel.vue
+++ b/frontend/src/components/project/TechnicalSpecsPanel.vue
@@ -55,7 +55,7 @@ import { Settings, ChevronDown, AlertCircle, RefreshCw } from 'lucide-vue-next'
 import { Button } from '@/components/ui/button'
 import { Badge } from '@/components/ui/badge'
 import { Collapsible, CollapsibleContent, CollapsibleTrigger } from '@/components/ui/collapsible'
-import { useAuthStore } from '@/stores/auth'
+import { usePermission } from '@/composables/usePermission'
 import { projectService, type ProjectTechnicalSpecs } from '@/services/project'
 import TechnicalSpecsDisplay from './TechnicalSpecsDisplay.vue'
 import DepartmentSpecsPanel from './DepartmentSpecsPanel.vue'
@@ -73,7 +73,7 @@ interface Emits {
 const props = defineProps<Props>()
 defineEmits<Emits>()
 
-const authStore = useAuthStore()
+const { isCoordinatorOrAdmin } = usePermission()
 
 // State
 const isOpen = ref(props.defaultOpen || false)
@@ -82,11 +82,7 @@ const error = ref<string | null>(null)
 const specs = ref<ProjectTechnicalSpecs | undefined>()
 
 // Computed properties
-const canEdit = computed(() => {
-  const userRole = authStore.userRole
-  const isAdmin = authStore.user?.is_admin
-  return userRole === 'coordinator' || isAdmin
-})
+const canEdit = computed(() => isCoordinatorOrAdmin.value)
 
 const hasSpecs = computed(() => {
   if (!specs.value) return false
diff --git a/frontend/src/components/shot/EditableTaskStatus.vue b/frontend/src/components/shot/EditableTaskStatus.vue
index 7945567..0b84d5c 100644
--- a/frontend/src/components/shot/EditableTaskStatus.vue
+++ b/frontend/src/components/shot/EditableTaskStatus.vue
@@ -169,8 +169,9 @@ import { User, Search, Check, X } from 'lucide-vue-next'
 import TaskStatusBadge from '@/components/task/TaskStatusBadge.vue'
 import { TaskStatus } from '@/services/shot'
 import { taskService } from '@/services/task'
-import { projectService, type ProjectMember } from '@/services/project'
+import type { ProjectMember } from '@/services/project'
 import { useTaskStatusesStore } from '@/stores/taskStatuses'
+import { useProjectMembersStore } from '@/stores/projectMembers'
 
 interface StatusOption {
   id: string
@@ -198,11 +199,12 @@ const emit = defineEmits<Emits>()
 
 // Use the shared task statuses store instead of direct API calls
 const taskStatusesStore = useTaskStatusesStore()
+const projectMembersStore = useProjectMembersStore()
 
 const isUpdating = ref(false)
 const isAssigning = ref(false)
-const isLoadingMembers = ref(false)
-const projectMembers = ref<ProjectMember[]>([])
+const projectMembers = computed<ProjectMember[]>(() => projectMembersStore.getMembers(props.projectId) || [])
+const isLoadingMembers = computed(() => projectMembersStore.isLoading(props.projectId))
 const searchQuery = ref('')
 
 // Filtered project members based on search query
@@ -306,27 +308,18 @@ const fetchStatuses = async () => {
   }
 }
 
-// Load project members
+// Load project members (shared cache across all EditableTaskStatus instances for this project)
 const loadProjectMembers = async () => {
-  if (projectMembers.value.length > 0) return // Already loaded
-  
-  isLoadingMembers.value = true
   try {
-    console.log('Loading project members for project:', props.projectId)
-    projectMembers.value = await projectService.getProjectMembers(props.projectId)
-    console.log('Loaded project members:', projectMembers.value)
+    await projectMembersStore.fetchProjectMembers(props.projectId)
   } catch (error) {
     console.error('Failed to load project members:', error)
-  } finally {
-    isLoadingMembers.value = false
   }
 }
 
 // Ensure members are loaded when popover is about to open
 const ensureMembersLoaded = () => {
-  console.log('Ensuring project members are loaded')
   if (projectMembers.value.length === 0) {
-    console.log('Loading project members on button click')
     loadProjectMembers()
   }
 }
@@ -407,7 +400,6 @@ onMounted(() => {
 // Refetch statuses when projectId changes
 watch(() => props.projectId, () => {
   fetchStatuses()
-  // Clear project members when project changes
-  projectMembers.value = []
+  loadProjectMembers()
 })
 </script>
diff --git a/frontend/src/components/shot/ShotBrowser.vue b/frontend/src/components/shot/ShotBrowser.vue
index 54d8734..4d17ecf 100644
--- a/frontend/src/components/shot/ShotBrowser.vue
+++ b/frontend/src/components/shot/ShotBrowser.vue
@@ -449,44 +449,64 @@ const loadShots = async () => {
 
 const loadEpisodes = async () => {
   if (!props.projectId) return
-  
+
   try {
     const data = await episodeService.getEpisodes(props.projectId)
     episodes.value = data
   } catch (err) {
     console.error('Failed to load episodes:', err)
+    toast({
+      title: 'Failed to load episodes',
+      description: err instanceof Error ? err.message : 'Episode filtering may be unavailable',
+      variant: 'destructive'
+    })
   }
 }
 
 const loadTaskTypes = async () => {
   if (!props.projectId) return
-  
+
   try {
     const data = await customTaskTypeService.getAllTaskTypes(props.projectId)
     allTaskTypes.value = data.shot_task_types || []
   } catch (err) {
     console.error('Failed to load task types:', err)
+    toast({
+      title: 'Failed to load task types',
+      description: err instanceof Error ? err.message : 'Task columns may be unavailable',
+      variant: 'destructive'
+    })
   }
 }
 
 const loadTaskStatuses = async () => {
   if (!props.projectId) return
-  
+
   try {
     await taskStatusesStore.fetchProjectStatuses(props.projectId)
   } catch (err) {
     console.error('Failed to load task statuses:', err)
+    toast({
+      title: 'Failed to load task statuses',
+      description: err instanceof Error ? err.message : 'Task status options may be unavailable',
+      variant: 'destructive'
+    })
   }
 }
 
 const loadProjectContext = async () => {
   if (!props.projectId) return
-  
+
   try {
     const project = await projectService.getProject(props.projectId)
     projectContext.value = project
   } catch (err) {
     console.error('Failed to load project context:', err)
+    toast({
+      title: 'Failed to load project context',
+      description: err instanceof Error ? err.message : 'Some shot validation checks may be unavailable',
+      variant: 'destructive'
+    })
   }
 }
 
diff --git a/frontend/src/components/shot/ShotDetailPanel.vue b/frontend/src/components/shot/ShotDetailPanel.vue
index 950d164..b7084a5 100644
--- a/frontend/src/components/shot/ShotDetailPanel.vue
+++ b/frontend/src/components/shot/ShotDetailPanel.vue
@@ -21,7 +21,7 @@
             {{ formatStatus(shot.status) }}
           </Badge>
           <!-- Deletion status indicator for admins -->
-          <Badge v-if="authStore.isAdmin && shot.deleted_at" variant="destructive" class="text-xs flex-shrink-0">
+          <Badge v-if="isAdmin && shot.deleted_at" variant="destructive" class="text-xs flex-shrink-0">
             Deleted {{ formatDeletedDate(shot.deleted_at) }}
           </Badge>
         </template>
@@ -350,9 +350,9 @@ import TaskStatusBadge from '@/components/task/TaskStatusBadge.vue'
 import { shotService, ShotStatus, type Shot, type TaskStatusInfo } from '@/services/shot'
 import { taskService } from '@/services/task'
 import { projectService, type ProjectMember } from '@/services/project'
-import { useAuthStore } from '@/stores/auth'
 import { useTaskStatusesStore } from '@/stores/taskStatuses'
 import { useAvatarUrl } from '@/composables/useAvatarUrl'
+import { usePermission } from '@/composables/usePermission'
 
 // Use TaskStatusInfo from shot service instead of local Task interface
 interface Task extends TaskStatusInfo {
@@ -384,9 +384,9 @@ interface Emits {
 const props = defineProps<Props>()
 const emit = defineEmits<Emits>()
 
-const authStore = useAuthStore()
 const taskStatusesStore = useTaskStatusesStore()
 const { getAvatarUrl } = useAvatarUrl()
+const { isAdmin, isCoordinatorOrAdmin } = usePermission()
 
 // Reactive state
 const shot = ref<Shot | null>(null)
@@ -432,25 +432,17 @@ const taskStatusCounts = computed(() => {
 
 
 
-const canCreateTask = computed(() => {
-  return authStore.user?.role === 'coordinator' || authStore.user?.is_admin
-})
+const canCreateTask = computed(() => isCoordinatorOrAdmin.value)
 
-const canCreateNote = computed(() => {
-  return authStore.user?.role === 'coordinator' || authStore.user?.is_admin
-})
+const canCreateNote = computed(() => isCoordinatorOrAdmin.value)
 
-const canLinkAssets = computed(() => {
-  return authStore.user?.role === 'coordinator' || authStore.user?.is_admin
-})
+const canLinkAssets = computed(() => isCoordinatorOrAdmin.value)
 
 const canUploadReferences = computed(() => {
   return true // All users can upload references
 })
 
-const canEditDesign = computed(() => {
-  return authStore.user?.role === 'coordinator' || authStore.user?.is_admin
-})
+const canEditDesign = computed(() => isCoordinatorOrAdmin.value)
 
 const availableTaskTypes = computed(() => {
   const existingTypes = new Set(tasks.value.map(task => task.task_type))
diff --git a/frontend/src/components/task/TaskDetailPanel.vue b/frontend/src/components/task/TaskDetailPanel.vue
index 408355c..bb69552 100644
--- a/frontend/src/components/task/TaskDetailPanel.vue
+++ b/frontend/src/components/task/TaskDetailPanel.vue
@@ -320,6 +320,7 @@ const emit = defineEmits<{
 
 const { toast } = useToast()
 const authStore = useAuthStore()
+const { isCoordinatorOrAdmin } = usePermission()
 
 const task = ref<Task | null>(null)
 const loading = ref(false)
@@ -350,10 +351,7 @@ const canSubmitWork = computed(() => {
   )
 })
 
-const canReassign = computed(() => {
-  if (!authStore.user) return false
-  return authStore.user.is_admin || authStore.user.role === 'coordinator'
-})
+const canReassign = computed(() => isCoordinatorOrAdmin.value)
 
 async function loadTask() {
   loading.value = true
@@ -478,6 +476,7 @@ function getUserInitials(member: ProjectMember): string {
 }
 
 import { useAvatarUrl } from '@/composables/useAvatarUrl'
+import { usePermission } from '@/composables/usePermission'
 
 const { getAvatarUrl } = useAvatarUrl()
 
diff --git a/frontend/src/components/task/TaskList.vue b/frontend/src/components/task/TaskList.vue
index 96da93c..72531ba 100644
--- a/frontend/src/components/task/TaskList.vue
+++ b/frontend/src/components/task/TaskList.vue
@@ -299,7 +299,7 @@
 <script setup lang="ts">
 import { ref, computed, onMounted } from 'vue'
 import { useTasksStore } from '@/stores/tasks'
-import { useAuthStore } from '@/stores/auth'
+import { usePermission } from '@/composables/usePermission'
 import { AlertCircle, Clock, UserPlus, Loader2, Eye } from 'lucide-vue-next'
 import { Button } from '@/components/ui/button'
 import { Input } from '@/components/ui/input'
@@ -344,7 +344,7 @@ const emit = defineEmits<{
 }>()
 
 const tasksStore = useTasksStore()
-const authStore = useAuthStore()
+const { isCoordinatorOrAdmin } = usePermission()
 const { toast } = useToast()
 
 const searchQuery = ref('')
@@ -361,9 +361,7 @@ const assignmentDepartmentFilter = ref('all')
 const projectMembers = ref<ProjectMember[]>([])
 const assigningTask = ref(false)
 
-const canAssignTasks = computed(() => {
-  return authStore.user?.is_admin || authStore.user?.role === 'coordinator'
-})
+const canAssignTasks = computed(() => isCoordinatorOrAdmin.value)
 
 const showDepartmentFilter = computed(() => {
   return canAssignTasks.value
diff --git a/frontend/src/composables/useAsyncAction.ts b/frontend/src/composables/useAsyncAction.ts
new file mode 100644
index 0000000..99cab20
--- /dev/null
+++ b/frontend/src/composables/useAsyncAction.ts
@@ -0,0 +1,41 @@
+import type { Ref } from 'vue'
+
+interface UseAsyncActionOptions {
+  isLoading: Ref<boolean>
+  error: Ref<string | null>
+}
+
+interface RunOptions {
+  /** Fallback message shown when the error has no server-provided detail */
+  errorMessage: string
+  /** Whether to re-throw after recording the error (default true) */
+  rethrow?: boolean
+}
+
+/**
+ * Wraps the isLoading/error/try-catch-finally shape shared by most store actions:
+ * set loading, clear error, run fn, extract a message from an axios-shaped or
+ * plain Error on failure, log it, optionally re-throw, and always clear loading.
+ */
+export function useAsyncAction({ isLoading, error }: UseAsyncActionOptions) {
+  // Overloads so callers that don't pass `rethrow: false` keep a non-optional return type
+  function run<T>(fn: () => Promise<T>, options: RunOptions & { rethrow?: true }): Promise<T>
+  function run<T>(fn: () => Promise<T>, options: RunOptions & { rethrow: false }): Promise<T | undefined>
+  async function run<T>(fn: () => Promise<T>, options: RunOptions): Promise<T | undefined> {
+    const { errorMessage, rethrow = true } = options
+    try {
+      isLoading.value = true
+      error.value = null
+      return await fn()
+    } catch (err: any) {
+      error.value = err?.response?.data?.detail || (err instanceof Error ? err.message : errorMessage)
+      console.error(errorMessage, err)
+      if (rethrow) throw err
+      return undefined
+    } finally {
+      isLoading.value = false
+    }
+  }
+
+  return { run }
+}
diff --git a/frontend/src/composables/usePermission.ts b/frontend/src/composables/usePermission.ts
new file mode 100644
index 0000000..4783e42
--- /dev/null
+++ b/frontend/src/composables/usePermission.ts
@@ -0,0 +1,19 @@
+import { computed } from 'vue'
+import { useAuthStore } from '@/stores/auth'
+
+/**
+ * Shared role/admin checks for the dominant duplicated permission pattern
+ * (`is_admin || role === 'coordinator'`) found across ~15 components.
+ * Not a generic `can()` — a couple of call sites check genuinely different
+ * things (ownership, a third "developer" role) and are left as-is.
+ */
+export function usePermission() {
+  const authStore = useAuthStore()
+
+  const isAdmin = computed(() => !!authStore.user?.is_admin)
+  const isCoordinatorOrAdmin = computed(() =>
+    authStore.user?.role === 'coordinator' || !!authStore.user?.is_admin
+  )
+
+  return { isAdmin, isCoordinatorOrAdmin }
+}
diff --git a/frontend/src/router/index.ts b/frontend/src/router/index.ts
index 2cb4150..93ca169 100644
--- a/frontend/src/router/index.ts
+++ b/frontend/src/router/index.ts
@@ -1,6 +1,7 @@
 import { createRouter, createWebHistory } from 'vue-router'
 import type { RouteRecordRaw } from 'vue-router'
 import { useAuthStore } from '@/stores/auth'
+import { toast } from '@/components/ui/toast/use-toast'
 
 const routes: RouteRecordRaw[] = [
   // Public routes
@@ -192,12 +193,17 @@ const router = createRouter({
 router.beforeEach(async (to, from, next) => {
   const authStore = useAuthStore()
   
-  // Initialize auth if not already done
+  // Initialize auth if not already done. Note: initializeAuth() never throws — on
+  // failure it logs a warning and clears auth state internally — so we detect failure
+  // by checking whether we're still unauthenticated afterward, not via try/catch.
   if (!authStore.user && authStore.accessToken) {
-    try {
-      await authStore.initializeAuth()
-    } catch (error) {
-      console.error('Auth initialization failed:', error)
+    await authStore.initializeAuth()
+    if (!authStore.isAuthenticated) {
+      toast({
+        title: 'Session expired',
+        description: 'Please log in again to continue.',
+        variant: 'destructive'
+      })
     }
   }
   
diff --git a/frontend/src/stores/assets.ts b/frontend/src/stores/assets.ts
index 70de6f6..2b86aac 100644
--- a/frontend/src/stores/assets.ts
+++ b/frontend/src/stores/assets.ts
@@ -2,6 +2,54 @@ import { defineStore } from 'pinia'
 import { ref, computed } from 'vue'
 import { assetService, type Asset, type AssetCreate, type AssetUpdate, AssetCategory, TaskStatus } from '@/services/asset'
 
+// Shared optimistic-update helpers for a single asset's task status, used by both
+// updateTaskStatus and bulkUpdateTaskStatus — the two API calls they wrap are genuinely
+// different (single-task endpoint vs. a distinct bulk endpoint), so only the per-asset
+// snapshot/apply/rollback of local state is shared, not the outer functions themselves.
+interface AssetTaskStatusSnapshot {
+  taskStatus?: TaskStatus
+  taskDetailStatus?: TaskStatus
+  taskDetailTaskId?: number
+}
+
+function snapshotAssetTaskStatus(asset: Asset, taskType: string): AssetTaskStatusSnapshot {
+  const taskDetail = asset.task_details?.find(task => task.task_type === taskType)
+  return {
+    taskStatus: asset.task_status?.[taskType],
+    taskDetailStatus: taskDetail?.status,
+    taskDetailTaskId: taskDetail?.task_id
+  }
+}
+
+function applyAssetTaskStatus(asset: Asset, taskType: string, newStatus: TaskStatus) {
+  if (asset.task_status) {
+    asset.task_status[taskType] = newStatus
+  }
+  const taskDetail = asset.task_details?.find(task => task.task_type === taskType)
+  if (taskDetail) {
+    taskDetail.status = newStatus
+  }
+}
+
+function rollbackAssetTaskStatus(
+  asset: Asset,
+  taskType: string,
+  snapshot: AssetTaskStatusSnapshot,
+  options: { restoreTaskId?: boolean } = {}
+) {
+  if (asset.task_status && snapshot.taskStatus !== undefined) {
+    asset.task_status[taskType] = snapshot.taskStatus
+  }
+
+  const taskDetail = asset.task_details?.find(task => task.task_type === taskType)
+  if (taskDetail && snapshot.taskDetailStatus !== undefined) {
+    taskDetail.status = snapshot.taskDetailStatus
+    if (options.restoreTaskId && snapshot.taskDetailTaskId !== undefined) {
+      taskDetail.task_id = snapshot.taskDetailTaskId
+    }
+  }
+}
+
 export const useAssetsStore = defineStore('assets', () => {
   // State
   const assets = ref<Asset[]>([])
@@ -159,25 +207,11 @@ export const useAssetsStore = defineStore('assets', () => {
     if (assetIndex === -1) return
 
     const asset = assets.value[assetIndex]
-    
-    // Store original status for rollback
-    const originalStatus = asset.task_status?.[taskType]
-    const originalTaskDetail = asset.task_details?.find(task => task.task_type === taskType)
-    const originalTaskDetailStatus = originalTaskDetail?.status
-    
-    // Optimistic update - update the task status in the asset immediately
-    if (asset.task_status) {
-      asset.task_status[taskType] = newStatus
-    }
-    
-    // Update the task details if available
-    if (asset.task_details) {
-      const taskDetail = asset.task_details.find(task => task.task_type === taskType)
-      if (taskDetail) {
-        taskDetail.status = newStatus
-      }
-    }
-    
+
+    // Store original status for rollback, then apply the optimistic update
+    const snapshot = snapshotAssetTaskStatus(asset, taskType)
+    applyAssetTaskStatus(asset, taskType, newStatus)
+
     // Update the current asset if it's the same
     if (currentAsset.value?.id === assetId) {
       currentAsset.value = { ...asset }
@@ -216,19 +250,13 @@ export const useAssetsStore = defineStore('assets', () => {
       }
     } catch (error) {
       // Rollback optimistic update on error
-      if (asset.task_status && originalStatus !== undefined) {
-        asset.task_status[taskType] = originalStatus
-      }
-      
-      if (originalTaskDetail && originalTaskDetailStatus !== undefined) {
-        originalTaskDetail.status = originalTaskDetailStatus
-      }
-      
+      rollbackAssetTaskStatus(asset, taskType, snapshot)
+
       // Update the current asset if it's the same
       if (currentAsset.value?.id === assetId) {
         currentAsset.value = { ...asset }
       }
-      
+
       throw error
     }
   }
@@ -237,10 +265,7 @@ export const useAssetsStore = defineStore('assets', () => {
     if (assetIds.length === 0) return
 
     // Store original states for rollback
-    const originalStates = new Map<number, {
-      taskStatus?: TaskStatus
-      taskDetail?: { status: TaskStatus; task_id?: number }
-    }>()
+    const originalStates = new Map<number, AssetTaskStatusSnapshot>()
 
     // Optimistic updates
     for (const assetId of assetIds) {
@@ -248,30 +273,10 @@ export const useAssetsStore = defineStore('assets', () => {
       if (assetIndex === -1) continue
 
       const asset = assets.value[assetIndex]
-      
-      // Store original state
-      const originalTaskStatus = asset.task_status?.[taskType]
-      const originalTaskDetail = asset.task_details?.find(task => task.task_type === taskType)
-      originalStates.set(assetId, {
-        taskStatus: originalTaskStatus,
-        taskDetail: originalTaskDetail ? { 
-          status: originalTaskDetail.status, 
-          task_id: originalTaskDetail.task_id 
-        } : undefined
-      })
 
-      // Apply optimistic update
-      if (asset.task_status) {
-        asset.task_status[taskType] = newStatus
-      }
-      
-      if (asset.task_details) {
-        const taskDetail = asset.task_details.find(task => task.task_type === taskType)
-        if (taskDetail) {
-          taskDetail.status = newStatus
-        }
-      }
-      
+      originalStates.set(assetId, snapshotAssetTaskStatus(asset, taskType))
+      applyAssetTaskStatus(asset, taskType, newStatus)
+
       // Update current asset if it's the same
       if (currentAsset.value?.id === assetId) {
         currentAsset.value = { ...asset }
@@ -325,32 +330,18 @@ export const useAssetsStore = defineStore('assets', () => {
         if (assetIndex === -1) continue
 
         const asset = assets.value[assetIndex]
-        const originalState = originalStates.get(assetId)
-        
-        if (originalState) {
-          // Rollback task status
-          if (asset.task_status && originalState.taskStatus !== undefined) {
-            asset.task_status[taskType] = originalState.taskStatus
-          }
-          
-          // Rollback task detail
-          if (originalState.taskDetail) {
-            const taskDetail = asset.task_details?.find(task => task.task_type === taskType)
-            if (taskDetail) {
-              taskDetail.status = originalState.taskDetail.status
-              if (originalState.taskDetail.task_id !== undefined) {
-                taskDetail.task_id = originalState.taskDetail.task_id
-              }
-            }
-          }
+        const snapshot = originalStates.get(assetId)
+
+        if (snapshot) {
+          rollbackAssetTaskStatus(asset, taskType, snapshot, { restoreTaskId: true })
         }
-        
+
         // Update current asset if it's the same
         if (currentAsset.value?.id === assetId) {
           currentAsset.value = { ...asset }
         }
       }
-      
+
       throw error
     }
   }
diff --git a/frontend/src/stores/auth.ts b/frontend/src/stores/auth.ts
index 5f4e203..97ee275 100644
--- a/frontend/src/stores/auth.ts
+++ b/frontend/src/stores/auth.ts
@@ -2,6 +2,7 @@ import { defineStore } from 'pinia'
 import { ref, computed } from 'vue'
 import { authService } from '@/services/auth'
 import type { User, LoginCredentials, RegisterData, LoginResponse } from '@/types/auth'
+import { useAsyncAction } from '@/composables/useAsyncAction'
 
 export const useAuthStore = defineStore('auth', () => {
   // State
@@ -10,6 +11,7 @@ export const useAuthStore = defineStore('auth', () => {
   const refreshToken = ref<string | null>(localStorage.getItem('refresh_token'))
   const isLoading = ref(false)
   const error = ref<string | null>(null)
+  const { run } = useAsyncAction({ isLoading, error })
 
   // Getters
   const isAuthenticated = computed(() => !!accessToken.value && !!user.value)
@@ -18,43 +20,24 @@ export const useAuthStore = defineStore('auth', () => {
 
   // Actions
   const login = async (credentials: LoginCredentials): Promise<LoginResponse> => {
-    try {
-      isLoading.value = true
-      error.value = null
-      
+    return run(async () => {
       const response = await authService.login(credentials)
-      
+
       // Store tokens
       accessToken.value = response.access_token
       refreshToken.value = response.refresh_token
       localStorage.setItem('access_token', response.access_token)
       localStorage.setItem('refresh_token', response.refresh_token)
-      
+
       // Get user profile
       await getCurrentUser()
-      
+
       return response
-    } catch (err: any) {
-      error.value = err.response?.data?.detail || 'Login failed'
-      throw err
-    } finally {
-      isLoading.value = false
-    }
+    }, { errorMessage: 'Login failed' })
   }
 
   const register = async (data: RegisterData) => {
-    try {
-      isLoading.value = true
-      error.value = null
-      
-      const response = await authService.register(data)
-      return response
-    } catch (err: any) {
-      error.value = err.response?.data?.detail || 'Registration failed'
-      throw err
-    } finally {
-      isLoading.value = false
-    }
+    return run(() => authService.register(data), { errorMessage: 'Registration failed' })
   }
 
   const logout = async () => {
diff --git a/frontend/src/stores/episodes.ts b/frontend/src/stores/episodes.ts
index 231820e..7208df0 100644
--- a/frontend/src/stores/episodes.ts
+++ b/frontend/src/stores/episodes.ts
@@ -1,6 +1,7 @@
 import { defineStore } from 'pinia'
 import { ref, computed } from 'vue'
 import { episodeService, type Episode, type EpisodeCreate, type EpisodeUpdate } from '@/services/episode'
+import { useAsyncAction } from '@/composables/useAsyncAction'
 
 export const useEpisodesStore = defineStore('episodes', () => {
   // State
@@ -8,6 +9,7 @@ export const useEpisodesStore = defineStore('episodes', () => {
   const currentEpisode = ref<Episode | null>(null)
   const isLoading = ref(false)
   const error = ref<string | null>(null)
+  const { run } = useAsyncAction({ isLoading, error })
 
   // Getters
   const getEpisodeById = computed(() => {
@@ -24,30 +26,17 @@ export const useEpisodesStore = defineStore('episodes', () => {
 
   // Actions
   const fetchEpisodes = async (projectId?: number) => {
-    try {
-      isLoading.value = true
-      error.value = null
-      
-      if (projectId) {
-        episodes.value = await episodeService.getProjectEpisodes(projectId)
-      } else {
-        episodes.value = await episodeService.getEpisodes()
-      }
-    } catch (err) {
-      error.value = err instanceof Error ? err.message : 'Failed to fetch episodes'
-      throw err
-    } finally {
-      isLoading.value = false
-    }
+    return run(async () => {
+      episodes.value = projectId
+        ? await episodeService.getProjectEpisodes(projectId)
+        : await episodeService.getEpisodes()
+    }, { errorMessage: 'Failed to fetch episodes' })
   }
 
   const fetchEpisode = async (episodeId: number) => {
-    try {
-      isLoading.value = true
-      error.value = null
-      
+    return run(async () => {
       const episode = await episodeService.getEpisode(episodeId)
-      
+
       // Update the episode in the list if it exists
       const index = episodes.value.findIndex(e => e.id === episodeId)
       if (index !== -1) {
@@ -55,81 +44,51 @@ export const useEpisodesStore = defineStore('episodes', () => {
       } else {
         episodes.value.push(episode)
       }
-      
+
       currentEpisode.value = episode
       return episode
-    } catch (err) {
-      error.value = err instanceof Error ? err.message : 'Failed to fetch episode'
-      throw err
-    } finally {
-      isLoading.value = false
-    }
+    }, { errorMessage: 'Failed to fetch episode' })
   }
 
   const createEpisode = async (projectId: number, episodeData: EpisodeCreate) => {
-    try {
-      isLoading.value = true
-      error.value = null
-      
+    return run(async () => {
       const newEpisode = await episodeService.createEpisode(projectId, episodeData)
       episodes.value.push(newEpisode)
-      
       return newEpisode
-    } catch (err) {
-      error.value = err instanceof Error ? err.message : 'Failed to create episode'
-      throw err
-    } finally {
-      isLoading.value = false
-    }
+    }, { errorMessage: 'Failed to create episode' })
   }
 
   const updateEpisode = async (episodeId: number, episodeData: EpisodeUpdate) => {
-    try {
-      isLoading.value = true
-      error.value = null
-      
+    return run(async () => {
       const updatedEpisode = await episodeService.updateEpisode(episodeId, episodeData)
-      
+
       // Update the episode in the list
       const index = episodes.value.findIndex(e => e.id === episodeId)
       if (index !== -1) {
         episodes.value[index] = updatedEpisode
       }
-      
+
       // Update current episode if it's the same
       if (currentEpisode.value?.id === episodeId) {
         currentEpisode.value = updatedEpisode
       }
-      
+
       return updatedEpisode
-    } catch (err) {
-      error.value = err instanceof Error ? err.message : 'Failed to update episode'
-      throw err
-    } finally {
-      isLoading.value = false
-    }
+    }, { errorMessage: 'Failed to update episode' })
   }
 
   const deleteEpisode = async (episodeId: number) => {
-    try {
-      isLoading.value = true
-      error.value = null
-      
+    return run(async () => {
       await episodeService.deleteEpisode(episodeId)
-      
+
       // Remove the episode from the list
       episodes.value = episodes.value.filter(e => e.id !== episodeId)
-      
+
       // Clear current episode if it's the deleted one
       if (currentEpisode.value?.id === episodeId) {
         currentEpisode.value = null
       }
-    } catch (err) {
-      error.value = err instanceof Error ? err.message : 'Failed to delete episode'
-      throw err
-    } finally {
-      isLoading.value = false
-    }
+    }, { errorMessage: 'Failed to delete episode' })
   }
 
   const setCurrentEpisode = (episode: Episode | null) => {
diff --git a/frontend/src/stores/projectMembers.ts b/frontend/src/stores/projectMembers.ts
new file mode 100644
index 0000000..07980af
--- /dev/null
+++ b/frontend/src/stores/projectMembers.ts
@@ -0,0 +1,80 @@
+import { defineStore } from 'pinia'
+import { ref, computed } from 'vue'
+import { projectService, type ProjectMember } from '@/services/project'
+
+interface CachedProjectMembers {
+  data: ProjectMember[]
+  lastFetched: number
+}
+
+export const useProjectMembersStore = defineStore('projectMembers', () => {
+  const membersByProject = ref<Map<number, CachedProjectMembers>>(new Map())
+  const loading = ref<Set<number>>(new Set())
+
+  // In-flight request de-dup: concurrent callers for the same project share one promise
+  const inFlightRequests = new Map<number, Promise<ProjectMember[]>>()
+
+  const CACHE_DURATION = 5 * 60 * 1000
+
+  const getMembers = computed(() => {
+    return (projectId: number): ProjectMember[] | null => {
+      const cached = membersByProject.value.get(projectId)
+      if (!cached) return null
+
+      const now = Date.now()
+      if (now - cached.lastFetched > CACHE_DURATION) {
+        membersByProject.value.delete(projectId)
+        return null
+      }
+
+      return cached.data
+    }
+  })
+
+  const isLoading = computed(() => {
+    return (projectId: number): boolean => {
+      return loading.value.has(projectId)
+    }
+  })
+
+  async function fetchProjectMembers(projectId: number, force = false): Promise<ProjectMember[]> {
+    if (!force) {
+      const cached = getMembers.value(projectId)
+      if (cached) {
+        return cached
+      }
+    }
+
+    const existing = inFlightRequests.get(projectId)
+    if (existing) {
+      return existing
+    }
+
+    loading.value.add(projectId)
+
+    const request = (async () => {
+      try {
+        const data = await projectService.getProjectMembers(projectId)
+        membersByProject.value.set(projectId, { data, lastFetched: Date.now() })
+        return data
+      } finally {
+        loading.value.delete(projectId)
+        inFlightRequests.delete(projectId)
+      }
+    })()
+
+    inFlightRequests.set(projectId, request)
+    return request
+  }
+
+  function invalidateProject(projectId: number) {
+    membersByProject.value.delete(projectId)
+  }
+
+  return {
+    getMembers,
+    isLoading,
+    fetchProjectMembers,
+    invalidateProject
+  }
+})
diff --git a/frontend/src/stores/projects.ts b/frontend/src/stores/projects.ts
index 6ea82ad..4a03cfc 100644
--- a/frontend/src/stores/projects.ts
+++ b/frontend/src/stores/projects.ts
@@ -1,7 +1,8 @@
 import { defineStore } from 'pinia'
-import { ref, computed } from 'vue'
+import { ref, computed, markRaw } from 'vue'
 import { Film, Palette, Zap, Folder } from 'lucide-vue-next'
 import { projectService, type Project as ProjectType, type ProjectCreate, type ProjectUpdate } from '@/services/project'
+import { useAsyncAction } from '@/composables/useAsyncAction'
 
 export interface Project extends ProjectType {
   icon?: any
@@ -13,13 +14,14 @@ export const useProjectsStore = defineStore('projects', () => {
   const activeProject = ref<Project | null>(null)
   const isLoading = ref(false)
   const error = ref<string | null>(null)
+  const { run } = useAsyncAction({ isLoading, error })
 
   // Getters
   const allProjectsView: Project = {
     id: 0,
     name: 'All Projects',
     status: 'planning',
-    icon: Folder,
+    icon: markRaw(Folder),
     description: 'View all projects',
     created_at: '',
     updated_at: ''
@@ -83,105 +85,66 @@ export const useProjectsStore = defineStore('projects', () => {
         }
     }
     
-    return { ...project, icon }
+    return { ...project, icon: markRaw(icon) }
   }
 
   // Actions
   const fetchProjects = async () => {
-    try {
-      isLoading.value = true
-      error.value = null
+    return run(async () => {
       const fetchedProjects = await projectService.getUserProjects()
       projects.value = fetchedProjects.map(assignProjectIcon)
-    } catch (err) {
-      error.value = err instanceof Error ? err.message : 'Failed to fetch projects'
-      console.error('Failed to fetch projects:', err)
-    } finally {
-      isLoading.value = false
-    }
+    }, { errorMessage: 'Failed to fetch projects', rethrow: false })
   }
 
   const createProject = async (projectData: ProjectCreate) => {
-    try {
-      isLoading.value = true
-      error.value = null
+    return run(async () => {
       const newProject = await projectService.createProject(projectData)
       const projectWithIcon = assignProjectIcon(newProject)
       projects.value.push(projectWithIcon)
       return projectWithIcon
-    } catch (err) {
-      error.value = err instanceof Error ? err.message : 'Failed to create project'
-      console.error('Failed to create project:', err)
-      throw err
-    } finally {
-      isLoading.value = false
-    }
+    }, { errorMessage: 'Failed to create project' })
   }
 
   const updateProject = async (id: number, updates: ProjectUpdate) => {
-    try {
-      isLoading.value = true
-      error.value = null
+    return run(async () => {
       const updatedProject = await projectService.updateProject(id, updates)
       const projectWithIcon = assignProjectIcon(updatedProject)
-      
+
       const index = projects.value.findIndex(p => p.id === id)
       if (index !== -1) {
         projects.value[index] = projectWithIcon
-        
+
         // Update active project if it's the one being updated
         if (activeProject.value?.id === id) {
           activeProject.value = projectWithIcon
         }
       }
-      
+
       return projectWithIcon
-    } catch (err) {
-      error.value = err instanceof Error ? err.message : 'Failed to update project'
-      console.error('Failed to update project:', err)
-      throw err
-    } finally {
-      isLoading.value = false
-    }
+    }, { errorMessage: 'Failed to update project' })
   }
 
   const deleteProject = async (id: number) => {
-    try {
-      isLoading.value = true
-      error.value = null
+    return run(async () => {
       await projectService.deleteProject(id)
-      
+
       const index = projects.value.findIndex(p => p.id === id)
       if (index !== -1) {
         projects.value.splice(index, 1)
-        
+
         // If the removed project was active, switch to all projects view
         if (activeProject.value?.id === id) {
           activeProject.value = allProjectsView
         }
       }
-    } catch (err) {
-      error.value = err instanceof Error ? err.message : 'Failed to delete project'
-      console.error('Failed to delete project:', err)
-      throw err
-    } finally {
-      isLoading.value = false
-    }
+    }, { errorMessage: 'Failed to delete project' })
   }
 
   const getProject = async (id: number, includeMembers: boolean = false) => {
-    try {
-      isLoading.value = true
-      error.value = null
+    return run(async () => {
       const project = await projectService.getProject(id, includeMembers)
       return assignProjectIcon(project)
-    } catch (err) {
-      error.value = err instanceof Error ? err.message : 'Failed to fetch project'
-      console.error('Failed to fetch project:', err)
-      throw err
-    } finally {
-      isLoading.value = false
-    }
+    }, { errorMessage: 'Failed to fetch project' })
   }
 
   const setActiveProject = (project: Project) => {
diff --git a/frontend/src/stores/settings.ts b/frontend/src/stores/settings.ts
index 34c569b..e48d402 100644
--- a/frontend/src/stores/settings.ts
+++ b/frontend/src/stores/settings.ts
@@ -1,12 +1,14 @@
 import { defineStore } from 'pinia'
 import { ref, computed } from 'vue'
 import { settingsService, type UploadLimitResponse, type GlobalSetting } from '@/services/settings'
+import { useAsyncAction } from '@/composables/useAsyncAction'
 
 export const useSettingsStore = defineStore('settings', () => {
   const uploadLimit = ref<UploadLimitResponse | null>(null)
   const allSettings = ref<GlobalSetting[]>([])
   const loading = ref(false)
   const error = ref<string | null>(null)
+  const { run } = useAsyncAction({ isLoading: loading, error })
 
   // Computed
   const uploadLimitMB = computed(() => uploadLimit.value?.upload_limit_mb || 1000)
@@ -14,93 +16,47 @@ export const useSettingsStore = defineStore('settings', () => {
 
   // Actions
   async function fetchUploadLimit() {
-    try {
-      loading.value = true
-      error.value = null
+    return run(async () => {
       uploadLimit.value = await settingsService.getUploadLimit()
-    } catch (err: any) {
-      error.value = err.response?.data?.detail || 'Failed to fetch upload limit'
-      console.error('Error fetching upload limit:', err)
-    } finally {
-      loading.value = false
-    }
+    }, { errorMessage: 'Failed to fetch upload limit', rethrow: false })
   }
 
   async function updateUploadLimit(limitMB: number) {
-    try {
-      loading.value = true
-      error.value = null
+    return run(async () => {
       uploadLimit.value = await settingsService.updateUploadLimit({ upload_limit_mb: limitMB })
-    } catch (err: any) {
-      error.value = err.response?.data?.detail || 'Failed to update upload limit'
-      console.error('Error updating upload limit:', err)
-      throw err
-    } finally {
-      loading.value = false
-    }
+    }, { errorMessage: 'Failed to update upload limit' })
   }
 
   async function fetchAllSettings() {
-    try {
-      loading.value = true
-      error.value = null
+    return run(async () => {
       allSettings.value = await settingsService.getAllSettings()
-    } catch (err: any) {
-      error.value = err.response?.data?.detail || 'Failed to fetch settings'
-      console.error('Error fetching settings:', err)
-    } finally {
-      loading.value = false
-    }
+    }, { errorMessage: 'Failed to fetch settings', rethrow: false })
   }
 
   async function createSetting(setting: { setting_key: string; setting_value: string; description?: string }) {
-    try {
-      loading.value = true
-      error.value = null
+    return run(async () => {
       const newSetting = await settingsService.createSetting(setting)
       allSettings.value.push(newSetting)
       return newSetting
-    } catch (err: any) {
-      error.value = err.response?.data?.detail || 'Failed to create setting'
-      console.error('Error creating setting:', err)
-      throw err
-    } finally {
-      loading.value = false
-    }
+    }, { errorMessage: 'Failed to create setting' })
   }
 
   async function updateSetting(settingKey: string, update: { setting_value: string; description?: string }) {
-    try {
-      loading.value = true
-      error.value = null
+    return run(async () => {
       const updatedSetting = await settingsService.updateSetting(settingKey, update)
       const index = allSettings.value.findIndex(s => s.setting_key === settingKey)
       if (index !== -1) {
         allSettings.value[index] = updatedSetting
       }
       return updatedSetting
-    } catch (err: any) {
-      error.value = err.response?.data?.detail || 'Failed to update setting'
-      console.error('Error updating setting:', err)
-      throw err
-    } finally {
-      loading.value = false
-    }
+    }, { errorMessage: 'Failed to update setting' })
   }
 
   async function deleteSetting(settingKey: string) {
-    try {
-      loading.value = true
-      error.value = null
+    return run(async () => {
       await settingsService.deleteSetting(settingKey)
       allSettings.value = allSettings.value.filter(s => s.setting_key !== settingKey)
-    } catch (err: any) {
-      error.value = err.response?.data?.detail || 'Failed to delete setting'
-      console.error('Error deleting setting:', err)
-      throw err
-    } finally {
-      loading.value = false
-    }
+    }, { errorMessage: 'Failed to delete setting' })
   }
 
   function clearError() {
diff --git a/frontend/src/stores/taskStatuses.ts b/frontend/src/stores/taskStatuses.ts
index acd7ade..864d8eb 100644
--- a/frontend/src/stores/taskStatuses.ts
+++ b/frontend/src/stores/taskStatuses.ts
@@ -14,6 +14,9 @@ export const useTaskStatusesStore = defineStore('taskStatuses', () => {
   const loading = ref<Set<number>>(new Set())
   const error = ref<string | null>(null)
 
+  // In-flight request de-dup: concurrent callers for the same project share one promise
+  const inFlightRequests = new Map<number, Promise<AllTaskStatusesResponse>>()
+
   // Cache duration: 5 minutes
   const CACHE_DURATION = 5 * 60 * 1000
 
@@ -92,51 +95,39 @@ export const useTaskStatusesStore = defineStore('taskStatuses', () => {
       }
     }
 
-    // Check if already loading
-    if (loading.value.has(projectId)) {
-      // Wait for existing request to complete
-      return new Promise((resolve, reject) => {
-        const checkInterval = setInterval(() => {
-          if (!loading.value.has(projectId)) {
-            clearInterval(checkInterval)
-            const cached = getProjectStatuses.value(projectId)
-            if (cached) {
-              resolve(cached)
-            } else {
-              reject(new Error('Failed to load task statuses'))
-            }
-          }
-        }, 100)
-        
-        // Timeout after 10 seconds
-        setTimeout(() => {
-          clearInterval(checkInterval)
-          reject(new Error('Timeout waiting for task statuses'))
-        }, 10000)
-      })
+    // Share the in-flight request with any concurrent callers instead of re-fetching
+    const existing = inFlightRequests.get(projectId)
+    if (existing) {
+      return existing
     }
 
     loading.value.add(projectId)
     error.value = null
 
-    try {
-      const data = await customTaskStatusService.getAllStatuses(projectId)
-      
-      // Cache the result
-      projectStatuses.value.set(projectId, {
-        projectId,
-        data,
-        lastFetched: Date.now()
-      })
+    const request = (async () => {
+      try {
+        const data = await customTaskStatusService.getAllStatuses(projectId)
 
-      return data
-    } catch (err: any) {
-      error.value = err.response?.data?.detail || 'Failed to fetch task statuses'
-      console.error('Error fetching task statuses:', err)
-      throw err
-    } finally {
-      loading.value.delete(projectId)
-    }
+        // Cache the result
+        projectStatuses.value.set(projectId, {
+          projectId,
+          data,
+          lastFetched: Date.now()
+        })
+
+        return data
+      } catch (err: any) {
+        error.value = err.response?.data?.detail || 'Failed to fetch task statuses'
+        console.error('Error fetching task statuses:', err)
+        throw err
+      } finally {
+        loading.value.delete(projectId)
+        inFlightRequests.delete(projectId)
+      }
+    })()
+
+    inFlightRequests.set(projectId, request)
+    return request
   }
 
   // Invalidate cache for a project (useful after creating/updating/deleting statuses)
diff --git a/frontend/src/stores/tasks.ts b/frontend/src/stores/tasks.ts
index 9805fb5..e91ba7d 100644
--- a/frontend/src/stores/tasks.ts
+++ b/frontend/src/stores/tasks.ts
@@ -3,12 +3,14 @@ import { ref, computed } from 'vue'
 import { taskService, type Task, type TaskListItem } from '@/services/task'
 import { shotService, type Shot } from '@/services/shot'
 import { assetService, type Asset } from '@/services/asset'
+import { useAsyncAction } from '@/composables/useAsyncAction'
 
 export const useTasksStore = defineStore('tasks', () => {
   const tasks = ref<TaskListItem[]>([])
   const loading = ref(false)
   const error = ref<string | null>(null)
   const selectedTask = ref<Task | null>(null)
+  const { run } = useAsyncAction({ isLoading: loading, error })
 
   // Computed properties maintain existing store interface
   const myTasks = computed(() => {
@@ -48,9 +50,7 @@ export const useTasksStore = defineStore('tasks', () => {
     status?: string
     taskType?: string
   }) {
-    loading.value = true
-    error.value = null
-    try {
+    return run(async () => {
       // Always use optimized approach when projectId is available
       if (filters?.projectId) {
         // Use optimized approach: get both shots and assets with embedded task data
@@ -62,7 +62,7 @@ export const useTasksStore = defineStore('tasks', () => {
         // Extract tasks from embedded data in shots and assets
         const shotTasks = extractTasksFromShots(shots)
         const assetTasks = extractTasksFromAssets(assets)
-        
+
         // Combine all tasks
         let allTasks = [...shotTasks, ...assetTasks]
 
@@ -81,15 +81,9 @@ export const useTasksStore = defineStore('tasks', () => {
       } else {
         // Fallback to original task service only when no projectId is provided
         // This maintains backward compatibility for legacy usage
-        const response = await taskService.getTasks(filters)
-        tasks.value = response
+        tasks.value = await taskService.getTasks(filters)
       }
-    } catch (err: any) {
-      error.value = err.response?.data?.detail || 'Failed to fetch tasks'
-      console.error('Error fetching tasks:', err)
-    } finally {
-      loading.value = false
-    }
+    }, { errorMessage: 'Failed to fetch tasks', rethrow: false })
   }
 
   function extractTasksFromShots(shots: Shot[]): TaskListItem[] {
@@ -166,12 +160,10 @@ export const useTasksStore = defineStore('tasks', () => {
   }
 
   async function fetchTask(taskId: number) {
-    loading.value = true
-    error.value = null
-    try {
+    return run(async () => {
       const task = await taskService.getTask(taskId)
       selectedTask.value = task
-      
+
       // Update in tasks array if exists
       const index = tasks.value.findIndex(t => t.id === taskId)
       if (index !== -1) {
@@ -219,15 +211,9 @@ export const useTasksStore = defineStore('tasks', () => {
         }
         tasks.value.push(taskListItem)
       }
-      
+
       return task
-    } catch (err: any) {
-      error.value = err.response?.data?.detail || 'Failed to fetch task'
-      console.error('Error fetching task:', err)
-      throw err
-    } finally {
-      loading.value = false
-    }
+    }, { errorMessage: 'Failed to fetch task' })
   }
 
   async function updateTaskStatus(taskId: number, status: string) {
diff --git a/frontend/src/views/EpisodesView.vue b/frontend/src/views/EpisodesView.vue
index f693468..6b160bb 100644
--- a/frontend/src/views/EpisodesView.vue
+++ b/frontend/src/views/EpisodesView.vue
@@ -127,6 +127,7 @@ import {
 import { useToast } from '@/components/ui/toast/use-toast'
 import { useAuthStore } from '@/stores/auth'
 import { useProjectsStore } from '@/stores/projects'
+import { usePermission } from '@/composables/usePermission'
 import { episodeService, type Episode, type EpisodeCreate, type EpisodeUpdate } from '@/services/episode'
 import EpisodeList from '@/components/episode/EpisodeList.vue'
 import EpisodeForm from '@/components/episode/EpisodeForm.vue'
@@ -136,6 +137,7 @@ const router = useRouter()
 const route = useRoute()
 const { toast } = useToast()
 const authStore = useAuthStore()
+const { isCoordinatorOrAdmin } = usePermission()
 const projectsStore = useProjectsStore()
 
 // Reactive state
@@ -150,17 +152,9 @@ const isSubmitting = ref(false)
 const selectedProjectId = ref<number | null>(null)
 
 // Computed properties
-const canCreateEpisodes = computed(() => {
-  const userRole = authStore.userRole
-  const isAdmin = authStore.user?.is_admin
-  return userRole === 'coordinator' || isAdmin
-})
+const canCreateEpisodes = computed(() => isCoordinatorOrAdmin.value)
 
-const canDeleteEpisodes = computed(() => {
-  const userRole = authStore.userRole
-  const isAdmin = authStore.user?.is_admin
-  return userRole === 'coordinator' || isAdmin
-})
+const canDeleteEpisodes = computed(() => isCoordinatorOrAdmin.value)
 
 const availableProjects = computed(() => {
   return projectsStore.projects
diff --git a/frontend/src/views/ProjectSettingsView.vue b/frontend/src/views/ProjectSettingsView.vue
index 7db459a..63dcb85 100644
--- a/frontend/src/views/ProjectSettingsView.vue
+++ b/frontend/src/views/ProjectSettingsView.vue
@@ -184,6 +184,7 @@ import { Separator } from "@/components/ui/separator";
 import { Tabs, TabsContent, TabsList, TabsTrigger } from "@/components/ui/tabs";
 import { useProjectsStore } from "@/stores/projects";
 import { useAuthStore } from "@/stores/auth";
+import { usePermission } from "@/composables/usePermission";
 import { useToast } from "@/components/ui/toast/use-toast";
 import TechnicalSpecsManager from "@/components/project/TechnicalSpecsManager.vue";
 import ProjectEditForm from "@/components/project/ProjectEditForm.vue";
@@ -201,6 +202,7 @@ const route = useRoute();
 const router = useRouter();
 const projectsStore = useProjectsStore();
 const authStore = useAuthStore();
+const { isCoordinatorOrAdmin } = usePermission();
 const { toast } = useToast();
 
 // State
@@ -236,10 +238,7 @@ const userDepartment = computed(() => {
   return member?.department_role;
 });
 
-const canManageProject = computed(() => {
-  if (!authStore.user) return false;
-  return authStore.user.role === 'coordinator' || authStore.user.is_admin;
-});
+const canManageProject = computed(() => isCoordinatorOrAdmin.value);
 
 // Methods
 const loadProject = async () => {
diff --git a/frontend/src/views/ProjectsView.vue b/frontend/src/views/ProjectsView.vue
index 72a474f..04a4888 100644
--- a/frontend/src/views/ProjectsView.vue
+++ b/frontend/src/views/ProjectsView.vue
@@ -406,7 +406,7 @@ import {
 } from '@/components/ui/alert-dialog'
 import { useToast } from '@/components/ui/toast/use-toast'
 import { useProjectsStore } from '@/stores/projects'
-import { useAuthStore } from '@/stores/auth'
+import { usePermission } from '@/composables/usePermission'
 import ProjectMemberManagement from '@/components/project/ProjectMemberManagement.vue'
 import type { Project } from '@/stores/projects'
 import { apiClient } from '@/services/api'
@@ -414,7 +414,7 @@ import { apiClient } from '@/services/api'
 const router = useRouter()
 const { toast } = useToast()
 const projectsStore = useProjectsStore()
-const authStore = useAuthStore()
+const { isAdmin, isCoordinatorOrAdmin } = usePermission()
 
 // Reactive state
 const searchQuery = ref('')
@@ -456,15 +456,9 @@ const projectForm = ref({
 })
 
 // Computed properties
-const canCreateProjects = computed(() => {
-  const userRole = authStore.userRole
-  const isAdmin = authStore.user?.is_admin
-  return userRole === 'coordinator' || isAdmin
-})
+const canCreateProjects = computed(() => isCoordinatorOrAdmin.value)
 
-const canDeleteProjects = computed(() => {
-  return authStore.user?.is_admin
-})
+const canDeleteProjects = computed(() => isAdmin.value)
 
 const filteredProjects = computed(() => {
   let filtered = projectsStore.projects
@@ -499,6 +493,11 @@ const isDateRangeValid = computed(() => {
 // Methods
 const loadProjects = async () => {
   await projectsStore.fetchProjects()
+  // thumbnailBlobUrls is local to this component instance and starts empty on every
+  // mount, so thumbnails must be (re)loaded after every fetch — not just when the
+  // store's project list actually changes (the store persists across navigations,
+  // so re-fetching the same projects wouldn't otherwise re-trigger loading here).
+  loadAllThumbnails()
 }
 
 const selectProject = (project: Project) => {
@@ -764,11 +763,6 @@ const getProjectInitials = (name: string) => {
   return name.substring(0, 2).toUpperCase()
 }
 
-// Watch for projects changes to load thumbnails
-watch(() => projectsStore.projects, () => {
-  loadAllThumbnails()
-}, { deep: true })
-
 // Watch for start date changes to auto-update end date for new projects
 watch(() => projectForm.value.start_date, (newStartDate) => {
   // Only auto-update end date for new projects (not when editing)
diff --git a/frontend_tasks.md b/frontend_tasks.md
index c571b99..79c21d3 100644
--- a/frontend_tasks.md
+++ b/frontend_tasks.md
@@ -46,43 +46,56 @@ Derived from `frontend_report.md`. Checklist form for tracking progress — chec
 - `GET /assets/{id}` never returned `task_details` (schema didn't even declare the field) — unlike `GET /shots/{id}`, which already did. Broke the asset detail panel's task list and, transitively, every new create-task/note/reference/version feature. Fixed in `backend/schemas/asset.py` + `backend/routers/assets.py`.
 - `TaskBrowser.vue`'s `handleRowClick` is a no-op by design (single click reserved for selection) — the new row-actions menu's "View Details"/"Reassign" needed to emit `row-double-click` instead, which is what actually opens the panel.
 
-## Phase 3 — Unify controls
+## Phase 3 — Unify controls ✅ (done)
 
-- [ ] Extract `ColumnToggleList` component (built on `DropdownMenuCheckboxItem`, not hand-rolled div+Check) and point at it from:
-  - [ ] `components/ui/sidebar/SidebarColumnSwitch.vue`
-  - [ ] `components/shot/ShotTableToolbar.vue`
-  - [ ] `components/asset/AssetTableToolbar.vue`
-  - [ ] `components/task/TaskTableToolbar.vue`
-- [ ] Extract shared `EntityTableToolbar` (search, column-visibility trigger, detail-panel toggle, clear-filters) to de-duplicate the three toolbar files
-- [ ] Extract `SegmentedToggle` component for the three hand-built view-mode switches (shot grid/list/table, asset grid/list, task all/shots/assets)
-- [ ] Standardize delete confirmation on the shot pattern (`Dialog` + `Alert` + impact summary + type-to-confirm) for any cascading delete; fix asset's dialog to match or consciously keep it lighter
-- [ ] Swap hand-rolled checkbox-divs for real `Checkbox`/`DropdownMenuCheckboxItem` in:
-  - [ ] `SidebarColumnSwitch.vue`
-  - [ ] `ShotTableToolbar.vue`
-  - [ ] `AssetTableToolbar.vue`
-  - [ ] `TaskTableToolbar.vue`
-  - [ ] `ShotTaskStatusFilter.vue`
-  - [ ] `asset/TaskStatusFilter.vue`
-- [ ] Replace ad hoc `size="sm" class="h-8 w-8 p-0"` with `size="icon-sm"` across toolbar/browser icon buttons
-- [ ] Decide one convention (icon+label vs. icon-only+tooltip) for primary "create" CTAs and apply consistently (shot/asset create buttons currently lack tooltips project/episode create buttons have)
-- [ ] Standardize row-actions/bulk-actions on `DropdownMenu`/`DropdownMenuItem`; replace ad hoc `<button>` list in `components/task/TaskBulkActionsMenu.vue`
-- [ ] Extract `DetailPanelShell` (header/close button, loading state, error state, Tabs scaffold, slide-in transition) for `ShotDetailPanel.vue`, `AssetDetailPanel.vue`, `TaskDetailPanel.vue` to share; add missing error state to Task's panel
+- [x] Extract `ColumnToggleList` component and point at it from:
+  - [x] `components/ui/sidebar/SidebarColumnSwitch.vue`
+  - [x] `components/shot/ShotTableToolbar.vue`
+  - [x] `components/asset/AssetTableToolbar.vue`
+  - [x] `components/task/TaskTableToolbar.vue`
 
-## Phase 4 — Architecture & tooling investment
+  Built on a new `CheckableCommandItem` primitive (`Command`/`CommandItem` wrapping a decorative `Checkbox`) instead of `DropdownMenuCheckboxItem` — keeps `CommandInput` search (needed for task-type columns) and avoids the ARIA double-toggle bug already found and fixed in the dead `ShotColumnVisibilityControl.vue`.
+- [x] Shared toolbar pieces extracted as separate composable pieces rather than one monolithic `EntityTableToolbar` (scope decision, approved before implementation: shot/asset/task toolbars diverge enough — shot's 3-way view mode + bulk-create, asset's thumbnail toggle, task's different filter set — that a config-driven mega-component would be a leaky abstraction): `useDebouncedSearch` composable, `DetailPanelToggleButton.vue`, `ClearFiltersButton.vue`, `SegmentedToggle.vue`. All three toolbars now compose these instead of hand-rolled equivalents.
+- [x] `SegmentedToggle` component — done (shot grid/list/table, asset grid/list, task all/shots/assets).
+- [x] Delete confirmation — verified already consistent (Shot/Asset both use `Dialog`+`Alert`+impact-summary+type-to-confirm since Phase 1). Episode/Project deletes are simple client-side guards with no impact-summary fetch at all, so giving them one would be new feature work, not unification — left as-is (verification-only, no code change).
+- [x] Swap hand-rolled checkbox-divs for `CheckableCommandItem` in:
+  - [x] `SidebarColumnSwitch.vue`
+  - [x] `ShotTableToolbar.vue`
+  - [x] `AssetTableToolbar.vue`
+  - [x] `TaskTableToolbar.vue`
+  - [x] `ShotTaskStatusFilter.vue` / `asset/TaskStatusFilter.vue` — merged into one `components/shared/TaskStatusFilter.vue`
+- [x] Replace ad hoc `size="sm" class="h-8 w-8 p-0"` with `size="icon-sm"` — 24 occurrences across toolbars, detail panels, row-action triggers, and columns.ts render functions
+- [x] CTA convention: dense table toolbars (Shot/Asset create buttons) stay icon-only but now have the same `title` tooltip every sibling icon button already had; full-page views (Project/Episode "New X") standardized wording between header and empty-state instances
+- [x] Standardize row-actions/bulk-actions on `DropdownMenu`/`DropdownMenuItem` — `TaskBulkActionsMenu.vue`'s "Assign To" section now mirrors "Set Status"'s existing submenu instead of a hand-rolled `<button>` list
+- [x] Extract shared detail-panel shell for `ShotDetailPanel.vue`, `AssetDetailPanel.vue`, `TaskDetailPanel.vue`: `DetailPanelOverlay.vue` (slide-in transition + mobile `Sheet`), `DetailPanelHeader.vue`, `DetailPanelLoading.vue`, `DetailPanelError.vue`. The `Tabs` scaffold was deliberately *not* unified — tab sets genuinely differ per domain (5 vs. 3 vs. 4 tabs) and forcing a shared config would be the kind of premature abstraction this phase was meant to avoid. Added the previously-missing error state to `TaskDetailPanel.vue` (it had no `error` ref or error branch at all — a failed load rendered nothing).
 
-- [ ] Add a shared `useAsyncAction`-style composable (`isLoading`/`error`/`run(fn)`) and adopt it across `stores/*.ts` to cut repeated try/catch/finally boilerplate
-- [ ] Replace `stores/taskStatuses.ts`'s polling-based in-flight request de-dup (100ms `setInterval` loop, lines 96-117) with promise memoization
-- [ ] Extend a similar TTL/cache strategy to `stores/assets.ts`, `stores/tasks.ts`, `stores/projects.ts`, `stores/episodes.ts` (currently no caching — every view re-fetches on mount)
-- [ ] De-duplicate `assets.ts`'s optimistic-update/rollback logic between single (`lines 156-234`) and bulk (`lines 236-356`) task-status updates into one parameterized function
-- [ ] Add `markRaw()` around icon components stored in reactive state — `stores/projects.ts` `assignProjectIcon`
-- [ ] Audit `deep: true` watchers, especially `views/ProjectsView.vue:770` (watches the full, non-`markRaw`'d projects array)
-- [ ] Fix N+1 project-member fetch: hoist `getProjectMembers()` call out of `EditableTaskStatus.vue` (mounted per row × task-type column) into a shared store/cache or parent-passed prop
-- [ ] Add table virtualization (e.g. `@tanstack/vue-virtual`) to `ShotsDataTable.vue`, `AssetsDataTable.vue`, `TasksDataTable.vue`
-- [ ] Introduce a shared `EmptyState` component and standardize on `Skeleton` for loading states (currently: 5 files use `Skeleton`, 62 use ad hoc spinners; 31 files hand-roll empty-state text)
-- [ ] Add toast-on-error for currently-silent secondary loads: episodes/task-types/task-statuses/project-context in `ShotBrowser.vue` (lines 474-508), `stores/notifications.ts:fetchStats`, router auth-init failure (`router/index.ts:190-196`)
-- [ ] Centralize a `usePermission()`/`can()` composable to consolidate role/admin checks currently duplicated across ~20 components outside the router guard
-- [ ] Consider splitting the largest files into smaller pieces: `views/project/ShotDetailView.vue` (1658 lines), `views/admin/DeletedItemsManagementView.vue` (1279 lines), and evaluate a shared "entity browser" composable for `ShotBrowser.vue`/`AssetBrowser.vue`'s ~70% structural overlap
-- [ ] Move ad hoc domain types out of `services/*.ts` into `types/` for discoverability (currently only `auth.ts`, `notification.ts`, `activity.ts` live in `types/`)
+**Bugs found and fixed during verification (approved mid-implementation):**
+- Shot's episode filter and Asset's category filter had silently been left on the old hand-rolled checkbox pattern (visually identical to `CheckableCommandItem`, so it wasn't caught by screenshots alone) — converted along with everything else.
+- `ShotDetailPanel.vue`'s Tasks list built `assigned_user_name: undefined // Will be resolved if needed` and never actually resolved it, so every task always showed "Unassigned" regardless of real assignment; and its task-status `Badge` used a hardcoded 5-value switch instead of the same `TaskStatusBadge`/task-statuses-store the shot table uses, so colors/labels (including custom per-project statuses) could drift from the table. Fixed both, and added an avatar next to the assignee name to match the table's assignment control.
+
+## Phase 4 — Architecture & tooling investment ✅ (done, scoped)
+
+Scope was narrowed with the user before implementation: this pass covers the mechanical/low-risk items with a demonstrated, concrete problem behind each. Several checklist items below turned out to be either genuine new feature work, carry real regression risk on large already-working files, or would touch a very wide surface for a purely organizational payoff — those are called out as **deferred**, not silently dropped.
+
+- [x] Fix N+1 project-member fetch: new `stores/projectMembers.ts` (same Map+TTL+in-flight-promise-dedup pattern as `taskStatuses.ts`), both `EditableTaskStatus.vue` variants now use it instead of independently calling `projectService.getProjectMembers` per row × task-type column. Verified via network interception: one call per project load, not one per cell.
+- [x] Replace `stores/taskStatuses.ts`'s polling-based in-flight de-dup (100ms `setInterval` loop) with a stored in-flight `Promise` per project ID — same pattern applied to the new `projectMembers` store.
+- [x] Add `markRaw()` around icon components stored in reactive state — `stores/projects.ts` `assignProjectIcon` and the static `allProjectsView.icon`.
+- [x] Fix `views/ProjectsView.vue`'s deep watcher on the full projects array (only existed to trigger thumbnail loading) — replaced with a shallow watch keyed on project IDs. The other ~10 `deep: true` watchers found elsewhere were audited but not changed — each needs its own read to judge triviality, out of scope for this pass.
+- [x] Add a shared `useAsyncAction` composable (`{isLoading, error}` in, `run(fn, {errorMessage, rethrow})` out) — applied only where the shape was already a clean match with no divergence: `auth.ts` (`login`/`register`), `episodes.ts` (all 5 actions), `settings.ts` (all 6), and the plain fetch actions in `projects.ts` (5) and `tasks.ts` (`fetchTasks`/`fetchTask`). Left untouched: `user.ts`'s mutations (no `isLoading` flag — adding one would be new behavior), `notifications.ts` (chains a second async call), `assets.ts`'s optimistic updaters (different shape, see below), `auth.ts:logout` (intentionally swallows and always clears state).
+- [x] Extract `assets.ts`'s shared per-asset optimistic-update helper (`snapshotAssetTaskStatus`/`applyAssetTaskStatus`/`rollbackAssetTaskStatus`) used by both `updateTaskStatus` and `bulkUpdateTaskStatus` — the two outer functions stay separate since they call genuinely different API endpoints (single-task vs. a distinct bulk endpoint with its own response shape); only the local-state snapshot/apply/rollback was actually duplicated.
+- [x] Add `usePermission()` composable (`isAdmin`, `isCoordinatorOrAdmin`) and apply to the ~15 confirmed sites duplicating the `is_admin || role === 'coordinator'` check (`ShotDetailPanel.vue`, `TaskDetailPanel.vue`, `TaskList.vue`, `EpisodesView.vue`, `EpisodeDropdown.vue`, `ProjectsView.vue`, `ProjectSettingsView.vue`, `TechnicalSpecsPanel.vue`, `TechnicalSpecsManager.vue`, `AppSidebar.vue`, `ProjectSwitcher.vue`). Left untouched: `UserMenu.vue`'s three-way variant (adds a `developer` role check) and `NoteItem.vue`'s ownership check — genuinely different logic.
+- [x] Add toast-on-error for the silent secondary loads in `ShotBrowser.vue` (episodes/task-types/task-statuses/project-context) and the router's auth-init failure path. In fixing the latter, found and fixed a real bug: `router/index.ts`'s `try/catch` around `authStore.initializeAuth()` was dead code — that function never throws (it swallows its own errors and calls `logout()` internally) — so the catch could never fire. Replaced with a check of `authStore.isAuthenticated` after the call, which correctly detects the failure. **`stores/notifications.ts:fetchStats` was deliberately left as a silent `console.error`**: it's polled every 30s by `startPolling()`, and a destructive toast firing on every poll during a network blip would be worse UX than the silent failure it replaces — this deviates from the original checklist wording, flagging rather than silently skipping.
+
+**Bugs found and fixed during verification (approved mid-implementation):**
+- `ShotDetailPanel.vue` had a dead `authStore.isAdmin` check sitting right next to the ones consolidated into `usePermission()` — swapped to the composable's `isAdmin` for consistency while already in that file.
+- Found (not fixed — backend, out of scope): `GET /settings/upload-limit` 404s because `backend/routers/settings.py` declares its own `/settings` prefix and `main.py` adds another, so the real path is `/settings/settings/upload-limit`. Confirmed via direct backend curl; unrelated to any frontend change in this phase.
+
+**Deferred** (documented, not implemented — see the approved plan for full rationale):
+- [ ] Extend TTL caching to `stores/assets.ts`, `stores/tasks.ts`, `stores/projects.ts`, `stores/episodes.ts` — no demonstrated redundant-fetch problem for these stores (unlike task statuses/project members), and caching list data in a multi-user live-editing tool risks staleness bugs.
+- [ ] Add table virtualization (`@tanstack/vue-virtual`) to `ShotsDataTable.vue`, `AssetsDataTable.vue`, `TasksDataTable.vue` — real feature work with design decisions that interact with the existing frozen-column two-pane scroll-sync layout, not a mechanical cleanup.
+- [ ] Introduce a shared `EmptyState` component and standardize on `Skeleton` for loading states — both already exist (`ui/empty/EmptyState.vue`, `ui/skeleton/Skeleton.vue`) and are cheap to reach for going forward, but a full sweep of ~58 ad hoc spinner sites is out of scope for this pass.
+- [ ] Split `views/project/ShotDetailView.vue` (1658 lines) / `views/admin/DeletedItemsManagementView.vue` (1279 lines) and extract a shared "entity browser" composable for `ShotBrowser.vue`/`AssetBrowser.vue` — both files are live and wired, and the overlap between Shot/Asset browsers is only partial (episode vs. category filters, store vs. local state). Bigger regression risk than the payoff justifies bundling here.
+- [ ] Move domain types (`Shot`/`Asset`/`Task`/`Project`/`Episode`) out of `services/*.ts` into `types/` — mechanical but touches every import site for a purely organizational win; fix opportunistically when a file is substantially touched anyway, same approach as the `ApiError` helper below.
 
 ## Phase 5 — Testing & quality gates