feat: implement full authentication system with CSRF protection and email verification flow

app/api/auth/csrf/route.ts

@@ -0,0 +1,7 @@
+import { NextResponse } from 'next/server';
+import { generateCsrfToken } from '@/lib/csrf';
+
+export async function GET() {
+    const token = await generateCsrfToken();
+    return NextResponse.json({ csrfToken: token });
+}