refactor: remove face embedding architecture - single Qdrant _faces collection

- Delete FaceEmbeddingDb module (face_embedding_db.rs)
- Stub match_faces_iterative, generate_seed_embeddings, tmdb_match_handler
- Remove sync_trace_embeddings, populate_face_embeddings_to_qdrant
- Remove embedding from face.json output (face_processor.py)
- Remove embedding from PG UPDATE (store_traced_faces.py)
- Remove workspace traces staging (checkin.rs, qdrant_workspace.rs)
- Fix tests: add pose_angle to Face, hand_nodes to TkgResult

Disabled functions (need reimplement with _faces):
- match_faces_iterative (identity agent)
- generate_seed_embeddings (TMDb seeds)
- tmdb_match_handler (TMDb matching)
- cluster_face_embeddings, search_similar_faces
- merge_traces_within_cuts

src/api/identities.rs

@@ -180,11 +180,11 @@ async fn list_identities(
     })?;
 
 let sql = format!(
-        "SELECT id::int, uuid, name, metadata FROM {} WHERE status IS NULL OR status != 'merged' ORDER BY id DESC LIMIT $1 OFFSET $2",
+        "SELECT id::int, uuid, name, metadata, status, starred FROM {} WHERE status IS NULL OR status != 'merged' ORDER BY id DESC LIMIT $1 OFFSET $2",
         id_table
     );
 
-    let rows: Vec<(i32, uuid::Uuid, String, Option<serde_json::Value>)> = match sqlx::query_as(&sql)
+    let rows: Vec<(i32, uuid::Uuid, String, Option<serde_json::Value>, Option<String>, Option<bool>)> = match sqlx::query_as(&sql)
         .bind(page_size as i64)
         .bind(offset)
         .fetch_all(db.pool())
@@ -201,11 +201,16 @@ let sql = format!(
 
     let identities: Vec<IdentityResponse> = rows
         .into_iter()
-        .map(|r| IdentityResponse {
-            id: r.0,
-            identity_uuid: r.1.to_string().replace('-', ""),
-            name: r.2,
-            metadata: r.3,
+        .map(|r| {
+            IdentityResponse {
+                id: r.0,
+                identity_uuid: r.1.to_string().replace('-', ""),
+                name: r.2,
+                metadata: r.3,
+                status: r.4,
+                starred: r.5.unwrap_or(false),
+                file_uuids: vec![], // Removed N+1 query
+            }
         })
         .collect();
 
@@ -281,6 +286,9 @@ pub struct IdentityResponse {
     pub identity_uuid: String,
     pub name: String,
     pub metadata: Option<serde_json::Value>,
+    pub status: Option<String>,
+    pub starred: bool,
+    pub file_uuids: Vec<String>,
 }
 
 #[derive(Debug, Serialize)]