refactor: metadata store cleanup, SSE unification, mock metadata loading & login redirect fix (#18651)

## Summary
- **SSE unification**: Replaced 11 individual SSE effect components with
a single generic `MetadataStoreSSEEffect`
- **Metadata store cleanup**: Merged `metadataCollectionHashesState`
into `metadataStoreState` (currentCollectionHash / draftCollectionHash
per entity), moved `objectMetadataItemsSelector` to `object-metadata`
domain, converted `navigationMenuItemsState` to a derived selector
- **Naming clarity**: Renamed `isAppMetadataReadyState` →
`isMinimalMetadataReadyState`, `MetadataGater` → `MinimalMetadataGater`,
`useIsLogged` → `useHasAccessTokenPair`,
`patchMetadataStoreFromSSEEvent` now takes named object params
- **Mock metadata loading**: Added `generate-navigation-menu-items.ts`
script, rewrote `useLoadMockedMinimalMetadata` to load full
objects/fields/indexes/views/navItems from generated mock data, enabling
proper sign-in background rendering (table columns, view picker,
navigation)
- **Login/logout transitions**: `MinimalMetadataLoadEffect` manages
mocked↔real metadata transitions based on auth state,
`MainContextStoreProvider` computes context on auth pages for view
picker support
- **Login redirect fix**: `handleLoadWorkspaceAfterAuthentication` now
re-enables `isAppEffectRedirectEnabled` after `loadCurrentUser()`
completes, fixing the blocked post-login navigation
- **Dead code removal**: Deleted `useRefreshPageLayouts`,
`useApplyPageLayouts`, `useStaleMetadataEntities`,
`metadataCollectionHashesState`, and all individual SSE effects

## Test plan
- [x] Login from welcome page redirects to companies page
- [x] Logout transitions cleanly to mocked metadata on welcome page
- [x] Sign-in background shows table columns, view picker, and
navigation items
- [x] SSE events still update metadata store entries correctly
- [x] Navigation menu items persist across page refreshes
- [ ] CI: lint, typecheck, tests pass

packages/twenty-front/src/modules/views/components/ViewBar.tsx

@@ -1,6 +1,6 @@
 import { type ReactNode } from 'react';
-import { useParams } from 'react-router-dom';
 
+import { useRecordIndexContextOrThrow } from '@/object-record/record-index/contexts/RecordIndexContext';
 import { ObjectSortDropdownButton } from '@/object-record/object-sort-dropdown/components/ObjectSortDropdownButton';
 import { TopBar } from '@/ui/layout/top-bar/components/TopBar';
 import { QueryParamsFiltersEffect } from '@/views/components/QueryParamsFiltersEffect';
@@ -26,19 +26,27 @@ type ViewBarProps = {
   viewBarId: string;
   className?: string;
   optionsDropdownButton: ReactNode;
+  isReadOnly?: boolean;
 };
 
 export const ViewBar = ({
   viewBarId,
   className,
   optionsDropdownButton,
+  isReadOnly = false,
 }: ViewBarProps) => {
-  const { objectNamePlural } = useParams();
+  const { objectNamePlural } = useRecordIndexContextOrThrow();
 
   if (!objectNamePlural) {
     return;
   }
 
+  if (isReadOnly) {
+    return (
+      <TopBar className={className} leftComponent={<ViewPickerDropdown />} />
+    );
+  }
+
   return (
     <ObjectSortDropdownComponentInstanceContext.Provider
       value={{ instanceId: VIEW_SORT_DROPDOWN_ID }}