- Add RDEPUBReaderUIState struct for centralized UI state model
- Refactor RDEPUBReaderChromeCoordinator with makeUIState() and applyUIState()
- Remove direct UI updates from RDEPUBReaderAnnotationCoordinator
- Consolidate updateBookmarkChrome() into updateReaderChrome()
- Update RDEPUBReaderContext, Runtime, and LocationCoordinator
- Add reader problem fix development checklist documentation
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>