- Add time-rewind button next to star dashboard button
- Create VersionHistoryPanel with Changes, Versions, and Deleted tabs
- Implement localStorage tracking of user's last-seen board state
- Add visual diff highlighting: yellow glow for new shapes, dim grey for deleted
- Create DeletedShapesOverlay with floating indicator and restore options
- Integrate with R2 backups for version snapshots via /api/versions API
- Add permission system (admin, editor, viewer roles)
- Admins can revert to versions, editors can restore shapes
- Viewers can see history but cannot modify
🤖 Generated with [Claude Code](https://claude.com/claude-code)
Co-Authored-By: Claude <noreply@anthropic.com>
