Develop (#55)

feat: optimize dashboard/search UX and simplify extension architecture

Redesign Dashboard with compact tool grid and recently used tools
Improve TopBar search UX with Cmd/Ctrl+K shortcut and better history navigation
Reorganize project structure into src/
Migrate i18n from react-i18next to chrome.i18n
Remove runtime language switch and settings page
Remove HTML/Markdown conversion tools
Clean up unused code, dead animations, redundant comments, and imports
Improve component consistency with shadcn/ui patterns
Replace hardcoded strings/colors with i18n tokens and theme tokens
Add comprehensive project documentation and coding standards
Fix CI artifact upload workflow and multiple TypeScript/test issues

Includes various refactors, UI polish, i18n cleanup, CI improvements,
and maintenance updates across the codebase.

tailwind.config.js

@@ -1,14 +1,7 @@
 /** @type {import('tailwindcss').Config} */
 export default {
   darkMode: 'class',
-  content: [
-    './entrypoints/**/*.{js,ts,jsx,tsx}',
-    './components/**/*.{js,ts,jsx,tsx}',
-    './pages/**/*.{js,ts,jsx,tsx}',
-    './providers/**/*.{js,ts,jsx,tsx}',
-    './utils/**/*.{js,ts,jsx,tsx}',
-    './config/**/*.{js,ts,jsx,tsx}',
-  ],
+  content: ['./entrypoints/**/*.{js,ts,jsx,tsx}', './src/**/*.{js,ts,jsx,tsx}'],
   theme: {
     extend: {
       colors: {