feat: Identity JSON sync mechanism

- storage.rs: add local_profile field, check disk for profile.jpg in save_identity_file_by_pool
- tmdb_api.rs: trigger JSON sync after TMDb probe
- identity_api.rs: upload_profile_image triggers JSON sync
- identity_binding.rs: bind/unbind/merge trigger JSON sync
- get_identity_json: replace DB fallback with Lazy Sync (generates JSON from DB if missing)
- Fixes missing/obsolete JSON files for all identity mutations

src/api/identity_binding.rs

@@ -115,10 +115,9 @@ pub async fn bind_identity(
     })?;
 
     let uuid_clean = identity_uuid.replace('-', "");
-    if let Ok(ref db) = PostgresDb::init().await {
-        if let Err(e) = crate::core::identity::storage::save_identity_file(db, &uuid_clean).await {
-            tracing::warn!("[bind] Failed to save identity file for {}: {}", uuid_clean, e);
-        }
+    // Sync identity JSON file
+    if let Err(e) = crate::core::identity::storage::save_identity_file_by_pool(&db, &uuid_clean).await {
+        tracing::warn!("[bind] Failed to sync identity file for {}: {}", uuid_clean, e);
     }
 
     Ok(Json(ApiResponse {
@@ -136,6 +135,7 @@ pub async fn unbind_identity(
     Json(req): Json<UnbindIdentityRequest>,
 ) -> Result<Json<ApiResponse<serde_json::Value>>, (StatusCode, Json<serde_json::Value>)> {
     let table = crate::core::db::schema::table_name("face_detections");
+    let id_table = crate::core::db::schema::table_name("identities");
 
     let db = sqlx::PgPool::connect(&crate::core::config::DATABASE_URL)
         .await
@@ -146,6 +146,22 @@ pub async fn unbind_identity(
             )
         })?;
 
+    // Find the identity_id before unbinding to sync it later
+    let identity_id: Option<i64> = sqlx::query_scalar(&format!(
+        "SELECT identity_id FROM {} WHERE file_uuid = $1 AND face_id = $2 AND identity_id IS NOT NULL",
+        table
+    ))
+    .bind(&req.file_uuid)
+    .bind(&req.face_id)
+    .fetch_optional(&db)
+    .await
+    .map_err(|e| {
+        (
+            StatusCode::INTERNAL_SERVER_ERROR,
+            Json(serde_json::json!({"error": e.to_string()})),
+        )
+    })?;
+
     let result = sqlx::query(&format!(
         "UPDATE {} SET identity_id = NULL WHERE file_uuid = $1 AND face_id = $2",
         table
@@ -161,6 +177,24 @@ pub async fn unbind_identity(
         )
     })?;
 
+    // Sync the identity JSON if we found an identity
+    if let Some(id) = identity_id {
+        let uuid: Option<String> = sqlx::query_scalar(&format!(
+            "SELECT uuid::text FROM {} WHERE id = $1",
+            id_table
+        ))
+        .bind(id)
+        .fetch_optional(&db)
+        .await
+        .ok()
+        .flatten();
+        if let Some(identity_uuid) = uuid {
+            if let Err(e) = crate::core::identity::storage::save_identity_file_by_pool(&db, &identity_uuid).await {
+                tracing::warn!("[unbind] Failed to sync identity file for {}: {}", identity_uuid, e);
+            }
+        }
+    }
+
     Ok(Json(ApiResponse {
         success: true,
         message: format!("Unbound face {} from {}", req.face_id, req.file_uuid),
@@ -263,6 +297,18 @@ pub async fn merge_identities(
             })?;
     }
 
+    // Sync target identity JSON
+    let into_uuid_clean = req.into_uuid.replace('-', "");
+    if let Err(e) = crate::core::identity::storage::save_identity_file_by_pool(&db, &into_uuid_clean).await {
+        tracing::warn!("[merge] Failed to sync target identity file for {}: {}", into_uuid_clean, e);
+    }
+
+    // Delete source identity JSON if not keeping history
+    if !keep {
+        let from_uuid_clean = identity_uuid.replace('-', "");
+        let _ = crate::core::identity::storage::delete_identity_file(&from_uuid_clean);
+    }
+
     Ok(Json(ApiResponse {
         success: true,
         message: format!(