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/processing/mod.rs

@@ -0,0 +1,8 @@
+//! Video processing modules and logic
+
+pub mod decision;
+pub mod handlers;
+pub mod modules;
+
+pub use decision::*;
+pub use handlers::*;