refactor(twenty-front): unify Favorites and Workspace navigation menu item code (#18697)

## Summary

- Consolidate duplicated Favorites and Workspace navigation menu item
frontend code into a single unified codebase within
`navigation-menu-item/`
- Move all DnD-related code from `navigation/` module into
`navigation-menu-item/display/dnd/`, renaming `workspaceDndKit*` files
to `navigationMenuItemDndKit*`
- Unify duplicated components (DnD providers, DnD hooks, folder
components, orphan items, section shell) using a `NavigationSections`
enum to parameterize section-specific behavior
- Rename residual workspace-prefixed symbols
(`WorkspaceDndKitSortableItem`, `WorkspaceDndKitDroppableSlot`,
`useWorkspaceSectionItems`, etc.) to `navigationMenuItem`-prefixed
equivalents
- Clean `navigation/` module to only contain app-level concerns (drawer
layout, settings, routing)

### Key changes

| Before (duplicated) | After (unified) |
|---|---|
| `FavoritesDndKitProvider` + `WorkspaceDndKitProvider` |
`NavigationMenuItemDndKitProvider` with `section` prop |
| `useFavoritesDndKit` + `useWorkspaceDndKit` |
`useNavigationMenuItemDndKit(section)` |
| `FavoritesFolderItem` + `WorkspaceNavigationMenuItemsFolder` |
`NavigationMenuItemFolder` with `section` prop |
| `FavoritesOrphanItems` | `NavigationMenuItemOrphanItems` with
`section` prop |
| Separate section shells | Shared `NavigationMenuItemSection` with thin
wrappers |
| `WorkspaceDndKitSortableItem` | `NavigationMenuItemSortableItem` |
| `WorkspaceDndKitDroppableSlot` | `NavigationMenuItemDroppableSlot` |
| `useWorkspaceSectionItems` | `useNavigationMenuItemSectionItems` |
| `useWorkspaceFolderOpenState` | `useNavigationMenuItemFolderOpenState`
|

Net result: **~1650 lines deleted** across 51 files.

## Test plan

- [x] `npx nx typecheck twenty-front` passes
- [x] `npx nx lint twenty-front` passes (0 errors)
- [x] `npx nx test twenty-front` passes (763 suites, 4467 tests)
- [ ] Smoke test: Favorites section renders, DnD reorder works, folder
create/rename/delete works
- [ ] Smoke test: Workspace section renders, edit mode works, DnD
reorder works
- [ ] Smoke test: Add-to-navigation from side panel works for both
sections

Made with [Cursor](https://cursor.com)

packages/twenty-front/src/modules/side-panel/components/SidePanelLinkInfo.tsx

@@ -4,7 +4,7 @@ import { IconLink, IconWorld } from 'twenty-ui/display';
 import { LinkIconWithLinkOverlay } from '@/navigation-menu-item/display/link/components/LinkIconWithLinkOverlay';
 import { NavigationMenuItemType } from 'twenty-shared/types';
 import { useUpdateLinkInDraft } from '@/navigation-menu-item/edit/link/hooks/useUpdateLinkInDraft';
-import { useWorkspaceSectionItems } from '@/navigation-menu-item/display/hooks/useWorkspaceSectionItems';
+import { useNavigationMenuItemSectionItems } from '@/navigation-menu-item/display/hooks/useNavigationMenuItemSectionItems';
 import { selectedNavigationMenuItemInEditModeState } from '@/navigation-menu-item/common/states/selectedNavigationMenuItemInEditModeState';
 import { SidePanelPageInfoLayout } from '@/side-panel/components/SidePanelPageInfoLayout';
 import { sidePanelPageInfoState } from '@/side-panel/states/sidePanelPageInfoState';
@@ -24,7 +24,7 @@ export const SidePanelLinkInfo = () => {
   const selectedNavigationMenuItemInEditMode = useAtomStateValue(
     selectedNavigationMenuItemInEditModeState,
   );
-  const items = useWorkspaceSectionItems();
+  const items = useNavigationMenuItemSectionItems();
   const { updateLinkInDraft } = useUpdateLinkInDraft();
 
   const defaultLabel = t`Link label`;