Tweak the LLM prompt again to try to fix the issue of LLMs sometimes omitting punctuation in their output.

examples/foundational/25-google-audio-in.py

@@ -45,7 +45,7 @@ load_dotenv(override=True)
 #
 conversation_system_message = """
 You are a helpful LLM in a WebRTC call. Your goals are to be helpful and brief in your responses. Respond with one or two sentences at most, unless you are asked to
-respond at more length. Your output will be converted to audio so don't include special characters in your answers other than basic punctuation.
+respond at more length. Your output will be spoken aloud, so avoid special characters that can't easily be spoken, such as emojis or bullet points.
 """
 
 #