* feat(ui): redesign settings dialog with modern GNOME HIG styling
Completely redesign the settings dialog to follow GNOME Human Interface
Guidelines with a modern, card-based preference page layout:
UI/UX Improvements:
- Add PreferencesGroup and PreferenceRow custom widgets mimicking
libadwaita's AdwPreferencesPage pattern
- Implement proper visual hierarchy with card-style grouped sections
- Add comprehensive CSS stylesheet with theme-aware colors
- Use proper spacing, border-radius, and typography following HIG
- Add smooth reveal animations for settings applied notifications
- Improve status indicators with semantic colors (success/warning/error)
Technical Changes:
- Replace flat grid layout with scrollable content area
- Use ListBox rows for better accessibility and keyboard navigation
- Add proper Gdk version requirement to prevent version conflicts
- Consolidate model info display into a unified info card
- Improve code organization with dedicated section builder methods
Visual Features:
- Card-like preference groups with subtle borders and shadows
- Proper row hover states for interactive feedback
- Status color coding: green for success, yellow for warnings, red for errors
- Cleaner legend display for model download status
- Modern flat button styling for auxiliary actions
All 328 existing tests continue to pass.
* refactor(settings): simplify to Close-only button pattern
Remove Apply/Cancel buttons in favor of pure instant-apply UX:
- Settings now apply immediately when changed (auto-apply)
- Single Close button follows modern GNOME Settings pattern
- Remove redundant _revert_settings() and _show_settings_applied_message()
- Update docstring to reflect instant-apply design
This resolves the UX inconsistency where settings auto-applied
but also had Apply/Cancel buttons that were confusing.
* feat(ui): redesign Logs and About dialogs with GNOME HIG styling
Logs Dialog:
- Modern card-based filter bar with grouped controls
- Theme-aware log level colors (works in light/dark mode)
- Toolbar with icon buttons for Copy, Export, Clear actions
- Toast notifications for user feedback
- Close-only button pattern (consistent with settings)
About Dialog:
- Extract to separate about_dialog.py module
- Use standard Gtk.AboutDialog (GNOME recommended)
- Clean credits section with contributors and tech stack
- Remove emojis for cleaner professional look
- Better organized credit sections
Both dialogs now follow the same design language as the
Settings dialog redesign.
