Remove unnecessary _model ivar from Hathora TTS and STT services, using _settings.model instead.

src/pipecat/services/hathora/stt.py

@@ -101,8 +101,6 @@ class HathoraSTTService(SegmentedSTTService):
             ),
             **kwargs,
         )
-
-        self._model = model
         self._api_key = api_key or os.getenv("HATHORA_API_KEY")
         self._base_url = base_url
 
@@ -136,7 +134,7 @@ class HathoraSTTService(SegmentedSTTService):
             url = f"{self._base_url}"
 
             payload = {
-                "model": self._model,
+                "model": self._settings.model,
             }
 
             if self._settings.language is not None:

src/pipecat/services/hathora/tts.py

@@ -120,7 +120,6 @@ class HathoraTTSService(TTSService):
             ),
             **kwargs,
         )
-        self._model = model
         self._api_key = api_key or os.getenv("HATHORA_API_KEY")
         self._base_url = base_url
 
@@ -149,7 +148,7 @@ class HathoraTTSService(TTSService):
 
             url = f"{self._base_url}"
 
-            payload = {"model": self._model, "text": text}
+            payload = {"model": self._settings.model, "text": text}
 
             if self._settings.voice is not None:
                 payload["voice"] = self._settings.voice