Add audio flushing after sending text in RimeNonJsonTTSService

This update ensures that audio is flushed immediately after sending bare text to the WebSocket, improving the responsiveness of the Text-to-Speech service.

src/pipecat/services/rime/tts.py

@@ -833,6 +833,7 @@ class RimeNonJsonTTSService(InterruptibleTTSService):
                 # Send bare text (not JSON)
                 await self._get_websocket().send(text)
                 await self.start_tts_usage_metrics(text)
+                await self.flush_audio() 
 
             except Exception as e:
                 logger.error(f"{self} exception: {e}")