feat: 添加 PWA 支持

packages/frontend/src/main.ts

@@ -83,4 +83,14 @@ app.use(i18n); // 使用 i18n
     }
     app.mount('#app');
   }
+// --- PWA Service Worker Registration ---
+  if ('serviceWorker' in navigator) {
+    window.addEventListener('load', () => {
+      navigator.serviceWorker.register('/sw.js').then(registration => {
+        console.log('SW registered: ', registration);
+      }).catch(registrationError => {
+        console.log('SW registration failed: ', registrationError);
+      });
+    });
+  }
 })();