Refactored evaluation process for improved efficiency:

- Initial response set to null; Frontend now generates a list of anticipated stats;
- Background evaluation dynamically updates DB upon completion;
- Frontend actively monitors and finalizes upon stat evaluation completion.

src/pages/api/stats/user/[user].ts

@@ -0,0 +1,29 @@
+// Next.js API route support: https://nextjs.org/docs/api-routes/introduction
+import type {NextApiRequest, NextApiResponse} from "next";
+import {app} from "@/firebase";
+import {getFirestore, collection, getDocs, query, where, doc, setDoc, addDoc} from "firebase/firestore";
+import {withIronSessionApiRoute} from "iron-session/next";
+import {sessionOptions} from "@/lib/session";
+
+const db = getFirestore(app);
+
+export default withIronSessionApiRoute(handler, sessionOptions);
+
+async function handler(req: NextApiRequest, res: NextApiResponse) {
+	if (!req.session.user) {
+		res.status(401).json({ok: false});
+		return;
+	}
+
+	const {user} = req.query;
+	const q = query(collection(db, "stats"), where("user", "==", user));
+
+	const snapshot = await getDocs(q);
+
+	res.status(200).json(
+		snapshot.docs.map((doc) => ({
+			id: doc.id,
+			...doc.data(),
+		})),
+	);
+}