Improve VibeVoice and KugelAudio model support
Technical details:
- Add kugel-2 support as a VibeVoice KugelAudio variant
- Normalize KugelAudio v2 config fields for transformers 4.x compatibility
- Fix UnifiedDownloader alt_repo handling for VibeVoice Hindi tokenizer downloads
- Improve VibeVoice pause-tag tracing in custom character switching
- Update VibeVoice model registry and generated docs
diodiogod
1df7df8b77