Add applicationId to syncableEntity and fix syncApp deletion (#15170)

## Context
- All flatEntity should extend SyncableEntity
- SyncableEntity should now have applicationId and application relation
- Fix syncApp deletion, should now properly use migration v2 to delete
syncable entities

packages/twenty-server/src/engine/metadata-modules/flat-field-metadata/utils/generate-index-for-flat-field-metadata.util.ts

@@ -44,6 +44,7 @@ export const generateIndexForFlatFieldMetadata = ({
         universalIdentifier: indexId,
         updatedAt: createdAt,
         workspaceId,
+        applicationId: null,
       },
       flatObjectMetadata,
     },

packages/twenty-server/src/engine/metadata-modules/flat-field-metadata/utils/get-default-flat-field-metadata-from-create-field-input.util.ts

@@ -54,6 +54,7 @@ export const getDefaultFlatFieldMetadata = ({
     updatedAt: createdAt,
     isUIReadOnly: createFieldInput.isUIReadOnly ?? false,
     morphId: null,
+    applicationId: null,
     viewFilterIds: [],
     viewGroupIds: [],
   } as const satisfies FlatFieldMetadata;

packages/twenty-server/src/engine/metadata-modules/flat-field-metadata/utils/recompute-view-groups-on-enum-flat-field-metadata-is-nullable-update.util.ts

@@ -71,6 +71,7 @@ export const recomputeViewGroupsOnEnumFlatFieldMetadataIsNullableUpdate = ({
         updatedAt: createdAt,
         deletedAt: null,
         viewId,
+        applicationId: toFlatFieldMetadata.applicationId,
       });
     } else if (isDefined(emptyValueFlatViewGroup)) {
       sideEffectResult.flatViewGroupsToDelete.push(emptyValueFlatViewGroup);

packages/twenty-server/src/engine/metadata-modules/flat-field-metadata/utils/recompute-view-groups-on-flat-field-metadata-options-update.util.ts

@@ -109,6 +109,7 @@ export const recomputeViewGroupsOnFlatFieldMetadataOptionsUpdate = ({
           isVisible: true,
           fieldValue: option.value,
           position: viewGroupHighestPosition + createdOptionIndex + 1,
+          applicationId: fromFlatFieldMetadata.applicationId,
         };
       }),
   );