Show composition arcs and asset info in PropertyPanel

Prims with authored references or payloads get a section below the
prim header listing every list-op entry (explicit/add/prepend/append/
delete) with its asset path and target prim; a folder icon button
browses (USD/usdz/MaterialX/Alembic filter) and replaces the entry's
asset path, authored as one undoable whole-list-op swap into the edit
target. Prims with composed assetInfo get a read-only key/value section
(resolved paths shown in tooltips). PropertyPanel now receives the
IconManager for the browse button.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

src/ui/Application.cpp

@@ -111,6 +111,7 @@ bool Application::Initialize(const std::string& windowTitle, int width, int heig
     m_iconManager = std::make_unique<IconManager>();
     m_iconManager->Initialize(ResourcePath("resources/icons"), 24);
     m_sceneHierarchyPanel->SetIconManager(m_iconManager.get());
+    m_propertyPanel->SetIconManager(m_iconManager.get());
     m_viewportPanel->SetIconManager(m_iconManager.get());
     m_timelinePanel->SetIconManager(m_iconManager.get());
     m_stageEditorPanel->SetIconManager(m_iconManager.get());