Add PWA install badge for desktop and tablet (manifest, SW, Add to Home Screen).

Co-authored-by: Cursor <cursoragent@cursor.com>

frontend/src/main.tsx

@@ -2,8 +2,11 @@ import { StrictMode } from "react";
 import { createRoot } from "react-dom/client";
 import { BrowserRouter } from "react-router-dom";
 import App from "./App";
+import { registerServiceWorker } from "./pwa/install";
 import "./styles/app.css";
 
+registerServiceWorker();
+
 createRoot(document.getElementById("root")!).render(
   <StrictMode>
     <BrowserRouter>