v0.1.2

feat: mobile keyboard detection, SOA refactor, and improved docs

- Add mobile keyboard detection (auto-hide navigation buttons on Android)
- Refactor to service-oriented architecture (DocumentService, NavigationService, UIRenderService, KeyboardDetectionService)
- Improve type safety and error handling
- Add debug mode and logging utilities
- Update documentation: DEVELOPMENT.md, README, CHANGELOG, add DEBUG_MODE.md
- Fix potential memory leaks and ensure proper cleanup
- Enhance mobile experience and platform detection