feat: Update data service response structure to include savedIds

- Modified the return type of the data service method to include an optional `savedIds` array, enhancing the response structure for better tracking of saved records.
- This change improves the flexibility of the service by allowing clients to receive additional information about the saved entries.

backend-node/src/services/dataService.ts

@@ -1396,7 +1396,7 @@ class DataService {
     userId?: string,
     deleteOrphans: boolean = true
   ): Promise<
-    ServiceResponse<{ inserted: number; updated: number; deleted: number }>
+    ServiceResponse<{ inserted: number; updated: number; deleted: number; savedIds?: any[] }>
   > {
     try {
       // 테이블 접근 권한 검증