Identification cleanup (#17301)

# Introduction

following https://github.com/twentyhq/twenty/pull/17279
As we've finally identified all the syncable metadata entities, which
means they're expected to have non nullable applicationId and
universalIdentifier at pg_level we can remove previous retro comp
universalIdentifier fallbacking and update the dto too

~~This needs IdentifyRemainingEntitiesMetadataCommand and
MakeRemainingEntitiesUniversalIdentifierAndApplicationIdNotNullableMigrationCommand
to be run~~
```ts
[Nest] 197  - 01/21/2026, 3:08:35 PM     LOG [MakeRemainingEntitiesUniversalIdentifierAndApplicationIdNotNullableMigrationCommand] Successfully run MakeRemainingEntitiesUniversalIdentifierAndApplicationIdNotNullableMigrationCommand
```

packages/twenty-server/src/engine/metadata-modules/flat-view-group/utils/from-create-view-group-input-to-flat-view-group-to-create.util.ts

@@ -29,8 +29,7 @@ export const fromCreateViewGroupInputToFlatViewGroupToCreate = ({
     createdAt: createdAt,
     updatedAt: createdAt,
     deletedAt: null,
-    universalIdentifier:
-      createViewGroupInput.universalIdentifier ?? viewGroupId,
+    universalIdentifier: createViewGroupInput.universalIdentifier ?? v4(),
     isVisible: createViewGroupInput.isVisible ?? true,
     fieldValue: createViewGroupInput.fieldValue,
     position: createViewGroupInput.position ?? 0,

packages/twenty-server/src/engine/metadata-modules/flat-view-group/utils/from-view-group-entity-to-flat-view-group.util.ts

@@ -17,8 +17,6 @@ export const fromViewGroupEntityToFlatViewGroup = (
     createdAt: viewGroupEntity.createdAt.toISOString(),
     updatedAt: viewGroupEntity.updatedAt.toISOString(),
     deletedAt: viewGroupEntity.deletedAt?.toISOString() ?? null,
-    universalIdentifier:
-      viewGroupEntityWithoutRelations.universalIdentifier ??
-      viewGroupEntityWithoutRelations.id,
+    universalIdentifier: viewGroupEntityWithoutRelations.universalIdentifier,
   };
 };