feat: Add control for how message content is split for TTS generation reqs

backend/config.py

@@ -1484,3 +1484,9 @@ AUDIO_TTS_VOICE = PersistentConfig(
     "audio.tts.voice",
     os.getenv("AUDIO_TTS_VOICE", "alloy"),  # OpenAI default voice
 )
+
+AUDIO_TTS_SPLIT_ON = PersistentConfig(
+    "AUDIO_TTS_SPLIT_ON",
+    "audio.tts.split_on",
+    os.getenv("AUDIO_TTS_SPLIT_ON", "punctuation"),
+)