Skip .part files in audio cache check

ingest.py

@@ -175,6 +175,9 @@ def main():
     print("=== Step 1: Download audio ===")
     audio_path = None
     for f in out_dir.glob("audio.*"):
+        if f.suffix == ".part":
+            print(f"  [skip] Ignoring partial download: {f}")
+            continue
         print(f"  [cache] Found existing audio: {f}")
         audio_path = f
         break