feat: added PWA support

templates/login.html

@@ -5,6 +5,12 @@
     <meta name="viewport" content="width=device-width, initial-scale=1.0">
     <title>Votify Web - Login</title>
     <link rel="icon" href="/static/favicon.ico" type="image/x-icon">
+    <link rel="manifest" href="/static/manifest.json">
+    <meta name="theme-color" content="#1db954">
+    <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="Votify Web">
+    <link rel="apple-touch-icon" href="/static/icons/icon-192x192.png">
     <style>
         * { margin: 0; padding: 0; box-sizing: border-box; }
         :root {
@@ -40,5 +46,12 @@
         <input type="password" name="password" placeholder="Password" autofocus required>
         <button type="submit">Sign In</button>
     </form>
+    <script>
+        if ('serviceWorker' in navigator) {
+            navigator.serviceWorker.register('/sw.js')
+                .then(reg => console.log('SW registered, scope:', reg.scope))
+                .catch(err => console.error('SW registration failed:', err));
+        }
+    </script>
 </body>
 </html>