- Restore auth on assets_serving.py using get_current_user_with_query_token
(supports ?token= query param for <audio> elements)
- Add proper MIME type detection on asset serving (fixes NotSupportedError)
- Use storage_paths for path resolution in assets_serving.py
- VoiceSelector: append auth token to preview URLs for /api/ endpoints
- VoiceAvatarPlaceholder: add authenticatedAudioUrl state with async token
resolution so <audio> elements get ?token= query param
- TestPersonaModal: same auth token pattern for voice preview audio