Fix _stop_current_speech doesn’t cancel LLM/TTS services.

core/duplex_pipeline.py

@@ -670,6 +670,12 @@ class DuplexPipeline:
             except asyncio.CancelledError:
                 pass
 
+        # Ensure underlying services are cancelled to avoid leaking work/audio
+        if self.tts_service:
+            await self.tts_service.cancel()
+        if self.llm_service and hasattr(self.llm_service, 'cancel'):
+            self.llm_service.cancel()
+        
         self._is_bot_speaking = False
         self._interrupt_event.clear()