Optimize shot table loading performance

- Pass episode_id filter to backend API instead of client-side filtering,
  reducing payload size when an episode is selected
- Skip getShot refetch in ShotDetailPanel when initialShot prop is provided
- Fix redundant DB query in list_shots: read project.custom_task_statuses
  directly from the already-fetched project object
- Add missing indexes on Task.shot_id, Task.assigned_user_id,
  Task.deleted_at and Episode.project_id; add add_perf_indexes.py
  migration script to apply them to existing databases
- Center login page layout
- Update CLAUDE.md and AGENTS.md with correct venv path

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

backend/routers/shots.py

@@ -266,9 +266,17 @@ async def list_shots(
         )
         for project in projects:
             custom_types = project.custom_shot_task_types or []
+            raw = project.custom_task_statuses
+            if isinstance(raw, str):
+                try:
+                    import json
+                    raw = json.loads(raw)
+                except (json.JSONDecodeError, TypeError):
+                    raw = []
+            custom_statuses = raw if isinstance(raw, list) else []
             project_data[project.id] = {
                 'task_types': STANDARD_SHOT_TASK_TYPES + custom_types,
-                'custom_statuses': get_project_custom_statuses(project.id, db)
+                'custom_statuses': custom_statuses
             }
     
     # OPTIMIZATION: Group results by shot and aggregate task data efficiently
@@ -606,6 +614,58 @@ async def get_shot(
     shot_data = ShotResponse.model_validate(shot)
     shot_data.task_count = task_count
     
+    # Add project_name from episode.project (already eager loaded)
+    if shot.episode and shot.episode.project:
+        shot_data.project_name = shot.episode.project.name
+    
+    # Add task status information (similar to list endpoint)
+    project = shot.episode.project if shot.episode else None
+    
+    # Get all task types: standard + custom
+    from routers.shots import STANDARD_SHOT_TASK_TYPES
+    project_task_types = list(STANDARD_SHOT_TASK_TYPES)  # Start with standard types
+    
+    if project and project.custom_shot_task_types:
+        custom_types = project.custom_shot_task_types or []
+        if isinstance(custom_types, list):
+            for ct in custom_types:
+                if isinstance(ct, dict) and 'type' in ct:
+                    project_task_types.append(ct['type'])
+                elif isinstance(ct, str):
+                    project_task_types.append(ct)
+    
+    # Initialize task_status and task_ids dictionaries
+    task_status_dict = {}
+    task_ids_dict = {}
+    task_details_list = []
+    
+    # Initialize with default not_started for all project task types
+    for task_type_init in project_task_types:
+        task_status_dict[task_type_init] = "not_started"
+    
+    # Build task information from active tasks
+    for task in active_tasks:
+        task_type = task.task_type.value if hasattr(task.task_type, 'value') else task.task_type
+        task_status = task.status.value if hasattr(task.status, 'value') else task.status
+        task_id = task.id
+        assigned_user_id = task.assigned_user_id
+        
+        # Update task status
+        task_status_dict[task_type] = task_status
+        task_ids_dict[task_type] = task_id
+        
+        # Add to task details
+        task_details_list.append(TaskStatusInfo(
+            task_type=task_type,
+            status=task_status,
+            task_id=task_id,
+            assigned_user_id=assigned_user_id
+        ))
+    
+    shot_data.task_status = task_status_dict
+    shot_data.task_ids = task_ids_dict
+    shot_data.task_details = task_details_list
+    
     return shot_data