notFound page added

react-project/src/pages/NotFound.jsx

@@ -0,0 +1,11 @@
+import { Link } from "react-router-dom";
+function NotFound() {
+  return (
+    <div>
+      <h1>404 — page introuvable</h1>
+      <Link to="/">Retour à l'accueil</Link>
+    </div>
+  );
+}
+
+export default NotFound;