feat: add PWA support with offline capabilities

- Add web app manifest with icons and theme configuration
- Add service worker with cache-first strategy for static assets
- Add useServiceWorker hook for SW registration
- Add PWA meta tags and Apple-specific tags to index.html
- Update vite.config.ts for optimal asset caching

index.html

@@ -4,6 +4,13 @@
     <meta charset="UTF-8" />
     <link rel="icon" type="image/svg+xml" href="/favicon.ico" />
     <meta name="viewport" content="width=device-width, initial-scale=1.0" />
+    <!-- PWA Meta Tags -->
+    <meta name="theme-color" content="#09090b" />
+    <meta name="apple-mobile-web-app-capable" content="yes" />
+    <meta name="apple-mobile-web-app-status-bar-style" content="black-translucent" />
+    <meta name="apple-mobile-web-app-title" content="Termix" />
+    <link rel="apple-touch-icon" href="/icons/512x512.png" />
+    <link rel="manifest" href="/manifest.json" />
     <title>Termix</title>
     <style>
       .hide-scrollbar {