Fix audioop backport package name

Use audioop-lts which is the correct PyPI package for Python 3.13+

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

requirements.txt

@@ -1,3 +1,3 @@
-pyaudioop
+audioop-lts
 gradio==4.44.0
 anthropic>=0.18.0