add completed monthly challenge alert to november 2025 challenge page

Author: adiati98

src/app/monthlychallenges/(challenges)/nov-2025/page.tsx

@@ -18,6 +18,11 @@ export const metadata = handle.meta;
 export default function Challenge() {
 	return (
 		<>
+			<div className="alert alert-success">
+				This monthly challenge is complete. Congratulations! Please join us for
+				the <Link href="/monthlychallenges/dec-2025">next challenge</Link>!
+			</div>
+
 			<h1>
 				<small>Monthly Challenge for November 2025:</small> Creative Community
 				Challenge