- Initial release of Scene Designer v1
- Added deterministic composition engine
- Added character editing with baseline tone controls
- Added timed event editing and timeline dragging
- Added aggregate and per-character tone preview
- Added JSON import and export using the canonical authored format
- Added validation for invalid scene/composition data
- Added README and INSTRUCTIONS documentation
- Fixed character rename input focus bug
- Prevented duplicate character ids from corrupting editor state
- Improved event labeling and dense timeline readability
- Stabilized overlapping-event dragging
- Clarified tone preview behavior
- Improved text JSON import handling