[refactor] Migrate manager code to DDD structure (#5662)

## Summary

Reorganized custom nodes manager functionality from scattered technical
layers into a cohesive domain-focused module following [domain-driven
design](https://en.wikipedia.org/wiki/Domain-driven_design) principles.

## Changes

- **What**: Migrated all manager code from technical layers
(`src/components/`, `src/stores/`, etc.) to unified domain structure at
`src/workbench/extensions/manager/`
- **Breaking**: Import paths changed for all manager-related modules
(40+ files updated)

## Review Focus

Verify all import path updates are correct and no circular dependencies
introduced. Check that [Vue 3 composition
API](https://vuejs.org/guide/reusability/composables.html) patterns
remain consistent across relocated composables.


┆Issue is synchronized with this [Notion
page](https://www.notion.so/PR-5662-refactor-Migrate-manager-code-to-DDD-structure-2736d73d3650812c87faf6ed0fffb196)
by [Unito](https://www.unito.io)

src/composables/useCoreCommands.ts

@@ -1,6 +1,5 @@
 import { useFirebaseAuthActions } from '@/composables/auth/useFirebaseAuthActions'
 import { useSelectedLiteGraphItems } from '@/composables/canvas/useSelectedLiteGraphItems'
-import { ManagerUIState, useManagerState } from '@/composables/useManagerState'
 import { useModelSelectorDialog } from '@/composables/useModelSelectorDialog'
 import {
   DEFAULT_DARK_COLOR_PALETTE,
@@ -41,12 +40,16 @@ import { useBottomPanelStore } from '@/stores/workspace/bottomPanelStore'
 import { useColorPaletteStore } from '@/stores/workspace/colorPaletteStore'
 import { useSearchBoxStore } from '@/stores/workspace/searchBoxStore'
 import { useWorkspaceStore } from '@/stores/workspaceStore'
-import { ManagerTab } from '@/types/comfyManagerTypes'
 import {
   getAllNonIoNodesInSubgraph,
   getExecutionIdsForSelectedNodes
 } from '@/utils/graphTraversalUtil'
 import { filterOutputNodes } from '@/utils/nodeFilterUtil'
+import {
+  ManagerUIState,
+  useManagerState
+} from '@/workbench/extensions/manager/composables/useManagerState'
+import { ManagerTab } from '@/workbench/extensions/manager/types/comfyManagerTypes'
 
 const moveSelectedNodesVersionAdded = '1.22.2'