Complete Android-first UI rebuild with mobile-first design system

Rebuild UI: complete redesign with accessibility, responsiveness, and bug fixes

feat: upgrade Android responsiveness, SEO, mobile UX across all frontend files

feat: complete data syncing, import/export, file manager, and chat history

feat: enhance mobile terminal, live preview imports, and theme settings

style: fix mobile responsiveness for android viewports

feat: redesign ui with themes, icons, toasts, and live preview

Create static/css/editor.css