Add backend and frontend structure with routing, components, and styling

- Implemented Express server with CORS and dotenv support
- Created basic routing with React Router in frontend
- Added Admin and Home components with navigation
- Integrated MainForm component for user input
- Updated package.json and package-lock.json with new dependencies
- Styled components using Tailwind CSS and Lucide icons
- Added error handling in server
- Created initial EJS view for backend

frontend/src/components/Admin.tsx

@@ -0,0 +1,11 @@
+import React from "react";
+
+const Admin: React.FC = () => {
+  return (
+    <>
+      <h1>Admin</h1>
+    </>
+  );
+};
+
+export default Admin;