fix: TKG rebuild type mismatch and face_track nodes

- Fix trace_id type mismatch (INT4 vs i64) with explicit ::bigint cast
- Change build_face_track_nodes to use from_pg version
- Add skin_tone_trace_nodes to API response
- Add #[derive(Serialize)] to TkgResult
- Fix Unicode panic in text label truncation
- Add push_existing_embeddings.py script

scripts/push_existing_embeddings.py

@@ -0,0 +1,87 @@
+#!/opt/homebrew/bin/python3.11
+"""
+Push existing embeddings from face.json to Qdrant _faces collection.
+This is faster than recomputing embeddings with face_processor.py.
+
+Usage:
+    python scripts/push_existing_embeddings.py --file-uuid <uuid>
+    python scripts/push_existing_embeddings.py --all
+"""
+
+import os
+import sys
+import json
+import argparse
+from pathlib import Path
+
+sys.path.insert(0, os.path.dirname(os.path.abspath(__file__)))
+from utils.qdrant_faces import (
+    ensure_faces_collection,
+    push_face_embeddings_batch,
+)
+
+OUTPUT_DIR = os.environ.get("MOMENTRY_OUTPUT_DIR", "/Users/accusys/momentry/output")
+
+
+def push_embeddings_for_file(file_uuid: str) -> int:
+    """Push embeddings from face.json to Qdrant"""
+    face_json_path = Path(OUTPUT_DIR) / f"{file_uuid}.face.json"
+    if not face_json_path.exists():
+        print(f"ERROR: {face_json_path} not found")
+        return 0
+    
+    with open(face_json_path) as f:
+        data = json.load(f)
+    
+    faces = []
+    for frame_data in data.get("frames", []):
+        frame = frame_data.get("frame", 0)
+        for face in frame_data.get("faces", []):
+            embedding = face.get("embedding")
+            if not embedding:
+                continue
+            
+            faces.append({
+                "frame": frame,
+                "trace_id": face.get("trace_id"),
+                "bbox": {
+                    "x": face.get("x", 0),
+                    "y": face.get("y", 0),
+                    "width": face.get("width", 0),
+                    "height": face.get("height", 0),
+                },
+                "confidence": face.get("confidence", 0),
+                "embedding": embedding,
+            })
+    
+    if faces:
+        count = push_face_embeddings_batch(file_uuid, faces)
+        print(f"Pushed {count} embeddings for {file_uuid}")
+        return count
+    
+    return 0
+
+
+def main():
+    parser = argparse.ArgumentParser(description="Push existing embeddings to Qdrant")
+    parser.add_argument("--file-uuid", help="File UUID to process")
+    parser.add_argument("--all", action="store_true", help="Process all files in output dir")
+    args = parser.parse_args()
+    
+    if args.all:
+        total = 0
+        for face_json in Path(OUTPUT_DIR).glob("*.face.json"):
+            # Extract UUID from filename like "uuid.face.json"
+            filename = face_json.name
+            file_uuid = filename.replace(".face.json", "")
+            count = push_embeddings_for_file(file_uuid)
+            total += count
+        print(f"\nTotal: {total} embeddings pushed")
+    elif args.file_uuid:
+        push_embeddings_for_file(args.file_uuid)
+    else:
+        parser.print_help()
+
+
+if __name__ == "__main__":
+    main()

src/api/trace_agent_api.rs

@@ -1002,6 +1002,7 @@ async fn rebuild_tkg(
                     "lip_track_nodes": r.lip_track_nodes,
                     "text_region_nodes": r.text_region_nodes,
                     "appearance_trace_nodes": r.appearance_trace_nodes,
+                    "skin_tone_trace_nodes": r.skin_tone_trace_nodes,
                     "accessory_nodes": r.accessory_nodes,
                     "object_nodes": r.object_nodes,
                     "hand_nodes": r.hand_nodes,

src/core/processor/tkg.rs

@@ -458,6 +458,7 @@ struct FaceDetectionRow {
 
 // ── Public API ────────────────────────────────────────────────────
 
+#[derive(Debug, Serialize)]
 pub struct TkgResult {
     pub face_track_nodes: usize,
     pub gaze_track_nodes: usize,
@@ -554,7 +555,7 @@ async fn build_face_track_nodes(
     file_uuid: &str,
     pose_data: &[FacePose],
 ) -> Result<usize> {
-    build_face_track_nodes_from_face_json(pool, file_uuid, pose_data).await
+    build_face_track_nodes_from_pg(pool, file_uuid, pose_data).await
 }
 
 async fn build_face_track_nodes_from_pg(
@@ -2228,8 +2229,8 @@ async fn build_text_region_nodes(pool: &PgPool, file_uuid: &str) -> Result<usize
         &rows
     {
         let external_id = format!("text_{}", chunk_id);
-        let label = if text.len() > 50 {
+        let label = if text.chars().count() > 50 {
-            format!("Text: {}...", &text[..47])
+            format!("Text: {}...", text.chars().take(47).collect::<String>())
         } else {
             format!("Text: {}", text)
         };
@@ -2587,7 +2588,7 @@ async fn build_skin_tone_trace_nodes(
     let mut count = 0;
 
     let rows: Vec<(i64, i64)> = sqlx::query_as(&format!(
-        "SELECT trace_id, COUNT(*) \
+        "SELECT trace_id::bigint, COUNT(*)::bigint \
          FROM {} \
          WHERE file_uuid = $1 AND trace_id IS NOT NULL \
          GROUP BY trace_id",