revert: restore working requirements.txt

Pinning transformers==5.3.0 risks conflicting with existing ComfyUI venv.
Back to permissive >=4.40.0 which worked in practice.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

requirements.txt

@@ -1,8 +1,5 @@
-transformers==5.3.0
+transformers>=4.40.0
 accelerate
 soundfile
 numpy
-pydub
-tensorboardx
-webdataset
 beautifulsoup4