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/api/identity_binding.rs

@@ -211,7 +211,7 @@ pub async fn get_signal_timeline(
 
 #[derive(Debug, Deserialize)]
 pub struct AVSuggestRequest {
-    pub video_uuid: String,
+    pub file_uuid: String,
     pub overlap_threshold: Option<f64>, // default 0.6
 }
 
@@ -233,7 +233,7 @@ pub async fn suggest_audio_visual_bindings(
 
     // 1. Get Face signals and their time ranges
     let face_signals = db
-        .list_unbound_signals(&req.video_uuid, "face")
+        .list_unbound_signals(&req.file_uuid, "face")
         .await
         .map_err(|e| {
             (
@@ -243,7 +243,7 @@ pub async fn suggest_audio_visual_bindings(
         })?;
 
     let speaker_signals = db
-        .list_unbound_signals(&req.video_uuid, "speaker")
+        .list_unbound_signals(&req.file_uuid, "speaker")
         .await
         .map_err(|e| {
             (
@@ -263,11 +263,11 @@ pub async fn suggest_audio_visual_bindings(
 
             // Placeholder: Calculate overlap by fetching timelines
             let face_timeline = db
-                .get_chunks_by_signal(&req.video_uuid, "face", face_id)
+                .get_chunks_by_signal(&req.file_uuid, "face", face_id)
                 .await
                 .unwrap_or_default();
             let speaker_timeline = db
-                .get_chunks_by_signal(&req.video_uuid, "speaker", speaker_id)
+                .get_chunks_by_signal(&req.file_uuid, "speaker", speaker_id)
                 .await
                 .unwrap_or_default();