Update changelog, mention text LLMs only

CHANGELOG.md

@@ -11,6 +11,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 - Added `pipecat.extensions.voicemail`, a module for detecting voicemail vs.
   live conversation, primarily intended for use in outbound calling scenarios.
+  The voicemail module is optimized for text LLMs only.
 
 - Added new frames to the `idle_timeout_frames` arg: `TranscriptionFrame`,
   `InterimTranscriptionFrame`, `UserStartedSpeakingFrame`, and

src/pipecat/extensions/voicemail/voicemail_detector.py

@@ -10,6 +10,9 @@ This module provides voicemail detection capabilities using parallel pipeline
 processing to classify incoming calls as either voicemail messages or live
 conversations. It's specifically designed for outbound calling scenarios where
 a bot needs to determine if a human answered or if the call went to voicemail.
+
+Note:
+    The voicemail module is optimized for text LLMs only.
 """
 
 import asyncio