second pass at issues. critical ones.

bincio/extract/cli.py

@@ -76,8 +76,7 @@ def _process_file(path: Path) -> dict:
 
     try:
         metrics = compute(activity)
-        activity_id = make_activity_id(activity)
-        write_activity(
+        activity_id = write_activity(
             activity, metrics, _output_dir,
             privacy=_privacy,
             rdp_epsilon=_rdp_epsilon,

bincio/extract/writer.py

@@ -90,6 +90,7 @@ def write_activity(
         if existing.get("source_hash") != activity.source_hash:
             activity_id = f"{activity_id}-{activity.source_hash[-6:]}"
             json_path = acts_dir / f"{activity_id}.json"
+            detail["id"] = activity_id
     json_path.write_text(json.dumps(detail, indent=2, ensure_ascii=False))
 
     # ── GeoJSON track ────────────────────────────────────────────────────────