chore(page-layout): remove IS_RECORD_PAGE_LAYOUT_* feature flags (#20556)

## Summary

- Both \`IS_RECORD_PAGE_LAYOUT_EDITING_ENABLED\` and
\`IS_RECORD_PAGE_LAYOUT_GLOBAL_EDITION_ENABLED\` are force-enabled on
every existing workspace by the 1.23.0 upgrade command
\`BackfillRecordPageLayoutsCommand\` and seeded enabled for new
workspaces via \`DEFAULT_FEATURE_FLAGS\` +
\`seed-feature-flags.util.ts\`. They are no longer load-bearing.
- Unwrap all \`if (flag) { … }\` conditionals to their enabled branch on
both server and front.
- Delete legacy fallback files that only the disabled branch reached:
\`PageLayoutRelationWidgetsSyncEffect\`,
\`usePageLayoutWithRelationWidgets\`,
\`reInjectDynamicRelationWidgetsFromDraft\`,
\`injectRelationWidgetsIntoLayout\`, \`isDynamicRelationWidget\` (and
their tests).
- Strip the two \`enableFeatureFlags\` calls from the 1.23 upgrade
command — the page-layout backfill data logic itself is kept intact
since old workspaces upgrading from < 1.23 still need it.
- No DB cleanup migration: stale \`featureFlag\` rows are left in place,
matching the precedent set by #20531 and #20460.

Net diff: 37 files, +106 / -1727.

## Test plan

- [x] \`npx nx typecheck twenty-shared twenty-server twenty-front\` —
all pass
- [x] \`npx nx lint:diff-with-main twenty-server twenty-front\` — all
pass
- [x] \`cd packages/twenty-front && npx jest page-layout\` — 1240 tests,
all pass
- [x] \`cd packages/twenty-server && npx jest
workspace-entity-manager.spec\` — pass
- [ ] Manual smoke: open a record page, verify tabs render and \"Edit
Layout\" command-menu action is available
- [ ] Manual smoke: Settings → Data model → object → Layout tab is
visible (and hidden for remote / Dashboard objects)
- [ ] Manual smoke: edit a tab title, save, reload — confirm persistence

packages/twenty-front/src/modules/page-layout/components/PageLayoutSingleTabRenderer.tsx

@@ -3,7 +3,6 @@ import { PageLayoutContent } from '@/page-layout/components/PageLayoutContent';
 import { PageLayoutEditModeProvider } from '@/page-layout/components/PageLayoutEditModeProvider';
 import { PageLayoutInitializationQueryEffect } from '@/page-layout/components/PageLayoutInitializationQueryEffect';
 import { PageLayoutRecordPageCustomizationSessionRegistrationEffect } from '@/page-layout/components/PageLayoutRecordPageCustomizationSessionRegistrationEffect';
-import { PageLayoutRelationWidgetsSyncEffect } from '@/page-layout/components/PageLayoutRelationWidgetsSyncEffect';
 import { PageLayoutContentProvider } from '@/page-layout/contexts/PageLayoutContentContext';
 import { useCurrentPageLayoutOrThrow } from '@/page-layout/hooks/useCurrentPageLayoutOrThrow';
 import { usePageLayoutTabWithVisibleWidgetsOrThrow } from '@/page-layout/hooks/usePageLayoutTabWithVisibleWidgetsOrThrow';
@@ -16,8 +15,6 @@ import { useLayoutRenderingContext } from '@/ui/layout/contexts/LayoutRenderingC
 import { useTargetRecord } from '@/ui/layout/contexts/useTargetRecord';
 import { TabListComponentInstanceContext } from '@/ui/layout/tab-list/states/contexts/TabListComponentInstanceContext';
 import { useAtomComponentStateValue } from '@/ui/utilities/state/jotai/hooks/useAtomComponentStateValue';
-import { useFeatureFlagsMap } from '@/workspace/hooks/useFeatureFlagsMap';
-import { FeatureFlagKey } from '~/generated-metadata/graphql';
 
 type PageLayoutSingleTabRendererProps = {
   pageLayoutId: string;
@@ -79,10 +76,6 @@ export const PageLayoutSingleTabRenderer = ({
 }: PageLayoutSingleTabRendererProps) => {
   const { targetRecordIdentifier, layoutType } = useLayoutRenderingContext();
 
-  const featureFlags = useFeatureFlagsMap();
-  const isRecordPageLayoutEditingEnabled =
-    featureFlags[FeatureFlagKey.IS_RECORD_PAGE_LAYOUT_EDITING_ENABLED];
-
   const tabListInstanceId = getTabListInstanceIdFromPageLayoutAndRecord({
     pageLayoutId,
     layoutType,
@@ -106,9 +99,6 @@ export const PageLayoutSingleTabRenderer = ({
         >
           <PageLayoutInitializationQueryEffect pageLayoutId={pageLayoutId} />
           <PageLayoutRecordPageCustomizationSessionRegistrationEffect />
-          {!isRecordPageLayoutEditingEnabled && (
-            <PageLayoutRelationWidgetsSyncEffect pageLayoutId={pageLayoutId} />
-          )}
           <PageLayoutSingleTabRendererContent />
         </PageLayoutEditModeProvider>
       </TabListComponentInstanceContext.Provider>