fix(ui): improve background handling and PWA update prompts

- Add adaptive solid color background support for dark/light themes.
- Replace mesh gradient with semi-transparent blurred background images.
- Fix background scrolling issue on mobile browsers.
- Remove borders from specific cards for consistent UI styling.
- Prevent caching of PWA service worker files in Nginx.
- Introduce interactive toast prompt for PWA updates instead of silent refresh.

vite-frontend/src/main.tsx

@@ -1,12 +1,42 @@
 import ReactDOM from "react-dom/client";
 import { BrowserRouter } from "react-router-dom";
 import { registerSW } from "virtual:pwa-register";
+import toast from "react-hot-toast";
 
 import App from "./App.tsx";
 import { Provider } from "./provider.tsx";
 import "@/styles/globals.css";
 
-registerSW({ immediate: true });
+const updateSW = registerSW({
+  immediate: true,
+  onNeedRefresh() {
+    toast(
+      (t) => (
+        <div className="flex flex-col gap-3">
+          <span className="text-sm font-medium text-foreground">发现新版本，是否立即刷新以应用更新？</span>
+          <div className="flex gap-2 justify-end">
+            <button
+              className="px-3 py-1.5 text-xs font-medium bg-primary text-primary-foreground hover:bg-primary/90 rounded-md transition-colors"
+              onClick={() => {
+                updateSW(true);
+                toast.dismiss(t.id);
+              }}
+            >
+              刷新
+            </button>
+            <button
+              className="px-3 py-1.5 text-xs font-medium bg-default-200 text-default-700 hover:bg-default-300 rounded-md transition-colors"
+              onClick={() => toast.dismiss(t.id)}
+            >
+              稍后
+            </button>
+          </div>
+        </div>
+      ),
+      { duration: Infinity, position: "bottom-right" }
+    );
+  },
+});
 
 ReactDOM.createRoot(document.getElementById("root")!).render(
   <BrowserRouter>