Files v2 - Add new FILES field type (#17236)

In this PR : 
- New field type FieldMetadataType.FILES added (as jsonb in DB)
- Backend: GraphQL types, validation, REST API schema, data processor
handling
- Frontend: field configuration in settings
- Feature flag IS_FILES_FIELD_ENABLED to gate the feature
- Integration tests for create/filter validation
- Dev seed: Feature flag enabled + FILES field on survey result object


To do in next PRs : 
- Backend : 
-- new workspaceFile controller (for download) & new workspaceFile
upload resolver (for upload)
-- pre-hook/post-hook to ensure fileId existence + listener to ensure
cleaning
- Frontend : FILES field display/edit in table view, record, ...

packages/twenty-server/src/engine/core-modules/open-api/utils/generate-random-field-value.util.ts

@@ -141,6 +141,10 @@ export const generateRandomFieldValue = ({
       return [];
     }
 
+    case FieldMetadataType.FILES: {
+      return null;
+    }
+
     case FieldMetadataType.TS_VECTOR: {
       throw new Error(
         `We should not generate fake version for ${field.type} field`,