Integrate relations for remote objects (#4754)

Foreign table id cannot be a foreign key of a base table. But the
current code use foreign keys to link object metadata with activities,
events... So we will:
- create a column without creating a foreign key
- add a comment on the table schema so pg_graphql sees it as a foreign
key

This PR:
- refactor a bit object metadata service so the mutation creation is
separated into an util
- adds the mutation creation for remote object relations
- add a new type of mutation to create a comment

---------

Co-authored-by: Thomas Trompette <thomast@twenty.com>

packages/twenty-server/src/engine/workspace-manager/workspace-migration-runner/workspace-migration-runner.service.ts

@@ -224,6 +224,14 @@ export class WorkspaceMigrationRunnerService {
             columnMigration.columnName,
           );
           break;
+        case WorkspaceMigrationColumnActionType.CREATE_COMMENT:
+          await this.createComment(
+            queryRunner,
+            schemaName,
+            tableName,
+            columnMigration.comment,
+          );
+          break;
         default:
           throw new Error(`Migration column action not supported`);
       }
@@ -412,4 +420,15 @@ export class WorkspaceMigrationRunnerService {
 
     return foreignKeys[0]?.constraint_name;
   }
+
+  private async createComment(
+    queryRunner: QueryRunner,
+    schemaName: string,
+    tableName: string,
+    comment: string,
+  ) {
+    await queryRunner.query(`
+      COMMENT ON TABLE "${schemaName}"."${tableName}" IS e'${comment}';
+    `);
+  }
 }