feat: add updatedBy field to track last record modifier (#16807)

<!-- CURSOR_SUMMARY -->
> [!NOTE]
> Implements last-modifier tracking and unified actor injection.
> 
> - New `ActorFromAuthContextService` replaces createdBy-only logic;
pre-query hooks now inject both `createdBy` and `updatedBy` on create
and `updatedBy` on update
> - Add `updatedBy` standard field to core/custom objects (e.g.,
`person`, `company`, `task`, `note`, `attachment`, `dashboard`,
`workflow`, `workflowRun`) with IDs, metadata builders, and ORM entity
fields
> - Record CRUD: `create` now sets both `createdBy` and `updatedBy`;
`update` sets `updatedBy`; workflow actions use a shared workflow actor
builder; REST base handler uses the new actor service
> - Seeder data and snapshots updated to include `updatedBy`; GraphQL
result formatting adds defaults/handling for empty composite fields
(incl. actor)
> - Frontend `useUpdateOneRecord` upserts returned record into the local
store after mutation
> 
> <sup>Written by [Cursor
Bugbot](https://cursor.com/dashboard?tab=bugbot) for commit
1f283778e9cb28a35bf84632a1a2997250bb3131. This will update automatically
on new commits. Configure
[here](https://cursor.com/dashboard?tab=bugbot).</sup>
<!-- /CURSOR_SUMMARY -->

---------

Co-authored-by: Félix Malfait <felix.malfait@gmail.com>
Co-authored-by: Félix Malfait <felix@twenty.com>

packages/twenty-server/src/engine/metadata-modules/object-metadata/utils/build-default-flat-field-metadatas-for-custom-object.util.ts

@@ -244,6 +244,42 @@ export const buildDefaultFlatFieldMetadatasForCustomObject = ({
     applicationId: applicationId ?? null,
   };
 
+  const updatedByFieldId = v4();
+  const updatedByField: FlatFieldMetadata<FieldMetadataType.ACTOR> = {
+    type: FieldMetadataType.ACTOR,
+    id: updatedByFieldId,
+    viewFieldIds: [],
+    mainGroupByFieldMetadataViewIds: [],
+    kanbanAggregateOperationViewIds: [],
+    calendarViewIds: [],
+    isLabelSyncedWithName: false,
+    isUnique: false,
+    objectMetadataId,
+    universalIdentifier: updatedByFieldId,
+    workspaceId,
+    standardId: CUSTOM_OBJECT_STANDARD_FIELD_IDS.updatedBy,
+    name: 'updatedBy',
+    label: 'Updated by',
+    icon: 'IconUserCircle',
+    description: 'The workspace member who last updated the record',
+    isNullable: false,
+    isActive: true,
+    isCustom: false,
+    isSystem: false,
+    isUIReadOnly: true,
+    defaultValue: { name: "''", source: "'MANUAL'" },
+    viewFilterIds: [],
+    createdAt,
+    updatedAt: createdAt,
+    options: null,
+    standardOverrides: null,
+    relationTargetFieldMetadataId: null,
+    relationTargetObjectMetadataId: null,
+    settings: null,
+    morphId: null,
+    applicationId: applicationId ?? null,
+  };
+
   const positionFieldId = v4();
   const positionField: FlatFieldMetadata<FieldMetadataType.POSITION> = {
     type: FieldMetadataType.POSITION,
@@ -327,6 +363,7 @@ export const buildDefaultFlatFieldMetadatasForCustomObject = ({
       nameField,
       createdAtField,
       updatedAtField,
+      updatedByField,
       deletedAtField,
       createdByField,
       positionField,