- Theme import/export with conflict resolution (overwrite/keep both/skip)
- Theme schema versioning: schemaVersion field, migrateIfNeeded on load with write-back
- Unit tests for theme decoding, migration, and round-trip (markdownViewrTests target)
- Max content width setting in General tab (checkbox + slider, default 1000px enabled)
- Homebrew cask: brew install --cask darinkelkhoff/tap/markdownviewr
- Copy button replaces Duplicate in Themes settings
- Settings min-width bumped to 560px
- Help updated for new features; CLAUDE.md documents migration process
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
