[异步播报打断]：完成播放中麦克风监听和音色隔离，包含后台监听、助手回放抑制和用户音色打断测试

src/owner_voice_pet/protocols.py

@@ -34,6 +34,7 @@ class AudioTransport(Protocol):
         *,
         chunk_ms: int,
         after_chunk: Callable[[AudioSegment, int], bool] | None = None,
+        should_stop: Callable[[], bool] | None = None,
     ) -> PlaybackResult:
         ...