feat: update core API, database layer, and worker modules

- Remove unused imports (n8n_search, universal_search, Client, Arc, etc.)
- Update API endpoints for identity, face recognition, search
- Fix postgres_db.rs search_videos parent_uuid column
- Add snapshot API and identity agent API
- Clean up backup files (.bak, .bak2)

src/core/db/mod.rs

@@ -41,9 +41,10 @@ pub mod sync_db;
 
 pub use mongodb_db::MongoDb;
 pub use postgres_db::{
-    Bm25Result, CandidateRecord, CreateApiKeyConfig, FileRecord, HybridSearchResult, MonitorJob,
-    MonitorJobStats, MonitorJobStatus, PostgresDb, ProcessorJobStatus, ProcessorResult,
-    ProcessorType, ResourceRecord, VideoRecord, VideoStatus,
+    Bm25Result, CandidateRecord, CreateApiKeyConfig, FileIdentityRecord, FileRecord,
+    HybridSearchResult, IdentityChunkRecord, IdentityDetailRecord, IdentityFaceRecord,
+    IdentityFileRecord, MonitorJob, MonitorJobStats, MonitorJobStatus, PostgresDb,
+    ProcessorJobStatus, ProcessorResult, ProcessorType, ResourceRecord, VideoRecord, VideoStatus,
 };
 pub use qdrant_db::{QdrantDb, VectorPayload};
 pub use redis_client::{