- Add dark mode with theme toggle, localStorage/cookie persistence, anti-FOUC script
- Add toast notification system with auto-dismiss and color-coded types
- Add api() fetch wrapper with auto JSON, X-Socket-ID, and error toasts
- Add keyboard shortcuts (/ search, b boards, ? help, n new card, Esc close)
- Add error page with status code and navigation
- Add focus trap utility and apply to CardModal with full ARIA dialog support
- Add hamburger menu for mobile, responsive columns, fullscreen card modal on mobile
- Add aria-labels to icon-only buttons and DnD live region
- Migrate all ~30 fetch calls to api() wrapper with success toasts
- Add dark: Tailwind variants to all 20+ pages and components
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
Catherine Renelle