Handle Deepgram SDK 6.x send_media() exceptions

Deepgram SDK 6.x surfaces connection errors from send_media() instead
of silently swallowing them. This causes error floods when the WebSocket
disconnects since every queued audio frame hits the dead connection.

Wrap send_media() in try/except: on failure, log one warning and set
self._connection = None so subsequent frames skip until the existing
_connection_handler reconnects.

src/pipecat/services/deepgram/stt.py

@@ -577,7 +577,11 @@ class DeepgramSTTService(STTService):
             Frame: None (transcription results come via WebSocket callbacks).
         """
         if self._connection:
-            await self._connection.send_media(audio)
+            try:
+                await self._connection.send_media(audio)
+            except Exception as e:
+                logger.warning(f"{self}: send_media failed, connection will reconnect: {e}")
+                self._connection = None
         yield None
 
     def _build_connect_kwargs(self) -> dict: