- Add to PluginManifest
- None = not declared (use VoiceLister fallback)
- () = explicitly no static voices
- Non-empty = static catalog available without Engine instantiation
- Update get_voices() to check manifest first, fall back to Engine
- Declare 54 Kokoro voices and 10 SuperTonic voices in manifests
- Remove hardcoded voice lists from engine.py files
- Engine.listVoices() now returns [] (manifest is source of truth)
- Clean up dead create_pipeline() kwargs (sample_rate, auto_download, total_steps)
- SuperTonic plugin uses internal defaults
- total_steps is per-request parameter via Pipeline.__call__() kwargs
- Add clear_preview_pipelines() for resource cleanup
- Fix test mocks to override listVoices()
- Update Architecture Amendment #1 doc
