feat: enhance embed block resizing, improve bookmark viewMode reactivity, and redesign tests panel UI
- Fixed bookmark block viewMode not updating on block changes by converting to setter/getter pattern with cached property
- Enhanced embed block with persistent resize handles using opacity transitions instead of DOM changes to prevent iframe flashing
- Improved YouTube URL handling to support watch, youtu.be, shorts, and embed formats with normalized embed URLs
- Added iframe permissions (
- Implemented multi-selection for notes with Ctrl+click, long-press, and keyboard shortcuts (Ctrl+A, Escape)
- Added Gemini API integration with environment configuration and routes
- Enhanced code block UI with improved copy feedback animation and visual polish
- Added sort order toggle (asc/desc) for note lists with persistent state
