Factorize from entity to flat entity utils (#21972)

## What

Factorizes the two responsibilities that were copy‑pasted across every
`from-<entity>-entity-to-flat-<entity>` util into two reusable tools.

### `fromEntityToScalarEntity`
Projects a TypeORM entity into its scalar flat shape using an
**allow‑list** driven by
`ALL_ENTITY_PROPERTIES_CONFIGURATION_BY_METADATA_NAME` (plus the base
columns `id`/`workspaceId`/`applicationId`/`universalIdentifier`). Only
registered scalar columns are forwarded, `Date`s are serialized to ISO
strings, and absent values are normalized to `null`. Replaces the
previous deny‑list (`removePropertiesFromRecord`) approach, so
unregistered/deprecated columns can no longer silently leak into the
flat entity.

### `resolveManyToOneRelationIdsToUniversalIdentifiers`
Resolves an entity's many‑to‑one foreign keys to their universal
identifiers, driven by `ALL_MANY_TO_ONE_METADATA_RELATIONS`. Handles the
always‑present `application`, nullable relations, and throws a
`FlatEntityMapsException` when a referenced id is missing from its
identifier map. Mirrors `resolveUniversalRelationIdentifiersToIds` in
the opposite direction.

Each `from-<entity>` util now reduces to: scalar spread + relation
spread (+ explicit one‑to‑many id/universalIdentifier arrays where
applicable).

### Note
The allow‑list drops `isUIReadOnly` (a `WasRemovedInUpgrade` column not
in the config) from `fieldMetadata`, which is the only
integration‑snapshot change.

<!-- This is an auto-generated description by cubic. -->
<a
href="https://cubic.dev/pr/twentyhq/twenty/pull/21972?utm_source=github"
target="_blank" rel="noopener noreferrer"
data-no-image-dialog="true"><picture><source
media="(prefers-color-scheme: dark)"
srcset="https://www.cubic.dev/buttons/review-in-cubic-dark.svg"><source
media="(prefers-color-scheme: light)"
srcset="https://www.cubic.dev/buttons/review-in-cubic-light.svg"><img
alt="Review in cubic"
src="https://www.cubic.dev/buttons/review-in-cubic-dark.svg"></picture></a>
<!-- End of auto-generated description by cubic. -->

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

@@ -1,40 +1,36 @@
-import { isDefined, removePropertiesFromRecord } from 'twenty-shared/utils';
+import { isDefined } from 'twenty-shared/utils';
 
-import {
-  FlatEntityMapsException,
-  FlatEntityMapsExceptionCode,
-} from 'src/engine/metadata-modules/flat-entity/exceptions/flat-entity-maps.exception';
-import { getMetadataEntityRelationProperties } from 'src/engine/metadata-modules/flat-entity/utils/get-metadata-entity-relation-properties.util';
+import { fromEntityToScalarEntity } from 'src/engine/metadata-modules/flat-entity/utils/from-entity-to-scalar-entity.util';
 import { type FlatObjectMetadata } from 'src/engine/metadata-modules/flat-object-metadata/types/flat-object-metadata.type';
 import { type FromEntityToFlatEntityArgs } from 'src/engine/workspace-cache/types/from-entity-to-flat-entity-args.type';
+import { resolveManyToOneRelationIdsToUniversalIdentifiers } from 'src/engine/workspace-manager/workspace-migration/universal-flat-entity/utils/resolve-many-to-one-relation-ids-to-universal-identifiers.util';
 
 type FromObjectMetadataEntityToFlatObjectMetadataArgs =
   FromEntityToFlatEntityArgs<'objectMetadata'> & {
     fieldMetadataIdToUniversalIdentifierMap: Map<string, string>;
   };
 
-export const fromObjectMetadataEntityToFlatObjectMetadata = ({
-  entity: objectMetadataEntity,
-  applicationIdToUniversalIdentifierMap,
-  fieldMetadataIdToUniversalIdentifierMap,
-}: FromObjectMetadataEntityToFlatObjectMetadataArgs): FlatObjectMetadata => {
-  const objectMetadataEntityWithoutRelations = removePropertiesFromRecord(
-    objectMetadataEntity,
-    getMetadataEntityRelationProperties('objectMetadata'),
-  );
+export const fromObjectMetadataEntityToFlatObjectMetadata = (
+  args: FromObjectMetadataEntityToFlatObjectMetadataArgs,
+): FlatObjectMetadata => {
+  const {
+    entity: objectMetadataEntity,
+    fieldMetadataIdToUniversalIdentifierMap,
+  } = args;
 
-  const applicationUniversalIdentifier =
-    applicationIdToUniversalIdentifierMap.get(
-      objectMetadataEntity.applicationId,
-    );
+  const objectMetadataScalarEntity = fromEntityToScalarEntity({
+    metadataName: 'objectMetadata',
+    entity: objectMetadataEntity,
+  });
 
-  if (!isDefined(applicationUniversalIdentifier)) {
-    throw new FlatEntityMapsException(
-      `Application with id ${objectMetadataEntity.applicationId} not found when building flat object metadata for object ${objectMetadataEntity.id}`,
-      FlatEntityMapsExceptionCode.ENTITY_NOT_FOUND,
-    );
-  }
+  const relationUniversalIdentifiers =
+    resolveManyToOneRelationIdsToUniversalIdentifiers({
+      metadataName: 'objectMetadata',
+      ...args,
+    });
 
+  // labelIdentifier/imageIdentifier are soft field references (not modeled
+  // relations) resolved without throwing on missing identifiers
   let labelIdentifierFieldMetadataUniversalIdentifier: string | null = null;
 
   if (isDefined(objectMetadataEntity.labelIdentifierFieldMetadataId)) {
@@ -70,11 +66,10 @@ export const fromObjectMetadataEntityToFlatObjectMetadata = ({
   }
 
   return {
-    ...objectMetadataEntityWithoutRelations,
-    universalIdentifier:
-      objectMetadataEntityWithoutRelations.universalIdentifier,
-    createdAt: objectMetadataEntity.createdAt.toISOString(),
-    updatedAt: objectMetadataEntity.updatedAt.toISOString(),
+    ...objectMetadataScalarEntity,
+    ...relationUniversalIdentifiers,
+    labelIdentifierFieldMetadataUniversalIdentifier,
+    imageIdentifierFieldMetadataUniversalIdentifier,
     viewIds: objectMetadataEntity.views.map(({ id }) => id),
     indexMetadataIds: objectMetadataEntity.indexMetadatas.map(({ id }) => id),
     searchFieldMetadataIds: objectMetadataEntity.searchFieldMetadatas.map(
@@ -86,9 +81,6 @@ export const fromObjectMetadataEntityToFlatObjectMetadata = ({
     ),
     fieldPermissionIds:
       objectMetadataEntity.fieldPermissions?.map(({ id }) => id) ?? [],
-    applicationUniversalIdentifier,
-    labelIdentifierFieldMetadataUniversalIdentifier,
-    imageIdentifierFieldMetadataUniversalIdentifier,
     fieldUniversalIdentifiers: objectMetadataEntity.fields.map(
       ({ universalIdentifier }) => universalIdentifier,
     ),