inworld: change set_voice uto use self._settings

Co-authored-by: Mark Backman <m.backman@gmail.com>

src/pipecat/services/inworld/tts.py

@@ -240,7 +240,7 @@ class InworldTTSService(TTSService):
             self._settings["temperature"] = params.temperature
 
         # Register voice and model with parent service for metrics and tracking
-        self.set_voice(params.voice_id or "Ashley")  # Used for logging and metrics
+        self.set_voice(self._settings["voice_id"])  # Used for logging and metrics
         self.set_model_name(params.model or "inworld-tts-1")  # Used for performance tracking
 
     def can_generate_metrics(self) -> bool: