fix(vad): model path aligned with Dockerfile (whisper_asr/silero_vad.onnx)

asr_agent/conversation_worker.py

@@ -345,7 +345,7 @@ class _TTSSegmenter:
 
 # ── VAD ──
 VAD_MODEL_PATH = os.environ.get("VAD_MODEL_PATH") or os.path.join(
-    os.path.dirname(os.path.abspath(__file__)), "silero_vad.onnx")
+    os.path.dirname(os.path.abspath(__file__)), "whisper_asr", "silero_vad.onnx")
 VAD_THRESHOLD_HIGH = float(os.environ.get("VAD_THRESHOLD_HIGH", "0.5"))
 VAD_THRESHOLD_LOW  = float(os.environ.get("VAD_THRESHOLD_LOW", "0.2"))
 VAD_WINDOW_SIZE    = int(os.environ.get("VAD_WINDOW_SIZE", "5"))