Migrate JavaScript to TypeScript with full type safety

- Rename all .js/.jsx files to .ts/.tsx across resources/js and theme dirs
- Add TypeScript 6.0 with strict mode, tsconfig.json
- Add type definitions for Inertia page props, Alpine.js, Turbolinks
- Update vite.config.js entries to .ts/.tsx extensions
- Update all Blade @vite() calls to match new .ts/.tsx entry points
- Add TypeScript ESLint config (replacing unused Vue plugin)
- Add @types/react, @types/react-dom, @types/lodash
- Add typecheck script and integrate into check pipeline
- Full tsc --noEmit, ESLint, and production build pass cleanly

resources/views/layouts/installation.blade.php

@@ -14,7 +14,7 @@
     <!-- Fonts -->
     <link rel="stylesheet" href="https://fonts.googleapis.com/css2?family=Nunito:wght@400;600;700&display=swap">
 
-    @vite(['resources/css/global.css', 'resources/js/global.js'], 'build')
+    @vite(['resources/css/global.css', 'resources/js/global.ts'], 'build')
     @stack('scripts')
 </head>