added Navbar + Footer + 404 page component

Author: QuadAces

frontend/src/pages/404.tsx

@@ -0,0 +1,11 @@
+import Footer from "@/components/Footer";
+import Navbar from "@/components/Navbar";
+
+export default function Custom404() {
+    return (
+        <>
+        <Navbar/>
+        <Footer/>
+        </>
+    )
+}