feat: implement success page and update routing; add lucide icons and enhance form submission feedback

frontend/src/App.tsx

@@ -1,12 +1,14 @@
 import "./App.css";
 import { BrowserRouter, Route, Routes } from "react-router-dom";
 import { MainForm } from "./pages/MainForm";
+import { SuccessPage } from "./pages/SuccessPage";
 
 function App() {
   return (
     <BrowserRouter>
       <Routes>
         <Route path="/" element={<MainForm />} />
+        <Route path="/success" element={<SuccessPage />} />
       </Routes>
     </BrowserRouter>
   );