fix: agent data_received handler + livekit config

agent/agent.py

@@ -1,10 +1,11 @@
 """
 Voice Agent — real-time voice assistant.
 
-Pipeline: Azure STT → Gemma LLM (xNAS, OpenAI-compatible) → Azure TTS (DragonHD)
+Pipeline: Azure STT → Gemma LLM (xNAS, OpenAI-compatible) → Azure TTS
 Runs inside the single Docker container alongside LiveKit server and web frontend.
 """
 
+import json
 import logging
 import os
 import textwrap
@@ -119,6 +120,9 @@ async def handle_job(ctx: JobContext) -> None:
 
     _active_session = session
 
+    # Listen for data messages (voice switching) from the web UI
+    ctx.room.on("data_received", _on_room_data)
+
     await session.start(
         agent=VoiceAssistant(),
         room=ctx.room,
@@ -138,13 +142,10 @@ async def handle_job(ctx: JobContext) -> None:
 # We listen on the room's data channel and update the TTS voice live.
 
 
-@server.event("room.data_received")
+def _on_room_data(packet) -> None:
-async def on_room_data(ctx: JobContext, payload: bytes) -> None:
     """Handle data messages from the web UI (voice selection)."""
-    import json
-
     try:
-        msg = json.loads(payload.decode("utf-8"))
+        msg = json.loads(packet.data.decode("utf-8"))
     except (json.JSONDecodeError, UnicodeDecodeError):
         return
 
@@ -153,8 +154,7 @@ async def on_room_data(ctx: JobContext, payload: bytes) -> None:
         if voice and _active_session:
             logger.info("Switching TTS voice to %s", voice)
             try:
-                # AgentSession exposes the TTS; update its options
+                tts = _active_session.tts
-                tts = _active_session._tts  # internal, but stable in 1.7
                 if hasattr(tts, "update_options"):
                     tts.update_options(voice=voice)
                     logger.info("Voice updated to %s", voice)