- Add theme switcher widget with Auto/Light/Dark options in header
- Implement manual theme override system with localStorage persistence
- Add complete button theme overrides for all variants (primary, outline-*)
- Fix missing focus states and placeholder colors for light theme
- Add proper alert styling for both themes
- Fix expression input error state colors in dark theme
- Complete comprehensive theme coverage for all UI elements
- Theme switcher overrides CSS media queries when manually selected
- All buttons, inputs, and surfaces now properly adapt to theme changes
Slawomir Koszewski
97d83923d9