Add performance optimizations and component refactors

- Cache read-heavy public API routes via redisCache (leaderboard, values,
  shop, articles, photos, guilds, teams, staff, users, home, radio, badges)
- Add single-flight and bounded-memory cache layer with unit tests
- Parallelize independent DB queries on search, rares, shop, staff, polls
  and profile pages
- Push radio points leaderboard aggregation to SQL with a LIMIT
- Split studio-client and import-furni-client into focused modules
- Clean up next.config.ts

src/app/api/radio/shouts/route.ts

@@ -2,6 +2,7 @@ import { desc, inArray } from "drizzle-orm";
 import { apiError, apiJson } from "@/lib/api";
 import { bearerUserId } from "@/lib/api-auth";
 import { db, RadioShouts, User } from "@/lib/db";
+import { apiCacheKey, redisCache } from "@/lib/redis-cache";
 
 // Latest 50 radio shouts with their author's username/look resolved. Mirrors the
 // query behind the public /radio/shouts page (radio_shouts ordered by created_at
@@ -10,41 +11,53 @@ import { db, RadioShouts, User } from "@/lib/db";
 // Max shout length (radio_shouts.message is TEXT; cap to keep posts sane).
 const MAX_MESSAGE_LENGTH = 255;
 
+// The shout feed is polled by the radio widget every few seconds — a short
+// cache keeps it cheap without delaying new shouts noticeably.
+const GET_TTL_SECONDS = 5;
+
 export async function GET(_req: Request) {
 	try {
-		const shouts = await db
-			.select({
-				id: RadioShouts.id,
-				userId: RadioShouts.userId,
-				message: RadioShouts.message,
-				createdAt: RadioShouts.createdAt,
-			})
-			.from(RadioShouts)
-			.orderBy(desc(RadioShouts.createdAt))
-			.limit(50);
+		const data = await redisCache(
+			apiCacheKey("radio:shouts"),
+			GET_TTL_SECONDS,
+			async () => {
+				const shouts = await db
+					.select({
+						id: RadioShouts.id,
+						userId: RadioShouts.userId,
+						message: RadioShouts.message,
+						createdAt: RadioShouts.createdAt,
+					})
+					.from(RadioShouts)
+					.orderBy(desc(RadioShouts.createdAt))
+					.limit(50);
 
-		// Resolve author usernames/looks. radio_shouts.user_id is an UnsignedBigInt
-		// while users.id is an Int, so narrow to Number for the lookup.
-		const authorIds = Array.from(new Set(shouts.map((s) => Number(s.userId))));
-		const authors = authorIds.length
-			? await db
-					.select({ id: User.id, username: User.username, look: User.look })
-					.from(User)
-					.where(inArray(User.id, authorIds))
-			: [];
-		const authorById = new Map(authors.map((a) => [a.id, a]));
+				// Resolve author usernames/looks. radio_shouts.user_id is an UnsignedBigInt
+				// while users.id is an Int, so narrow to Number for the lookup.
+				const authorIds = Array.from(
+					new Set(shouts.map((s) => Number(s.userId))),
+				);
+				const authors = authorIds.length
+					? await db
+							.select({ id: User.id, username: User.username, look: User.look })
+							.from(User)
+							.where(inArray(User.id, authorIds))
+					: [];
+				const authorById = new Map(authors.map((a) => [a.id, a]));
 
-		const data = shouts.map((s) => {
-			const author = authorById.get(Number(s.userId));
-			return {
-				id: s.id,
-				userId: s.userId,
-				username: author?.username ?? null,
-				look: author?.look ?? null,
-				message: s.message,
-				createdAt: s.createdAt,
-			};
-		});
+				return shouts.map((s) => {
+					const author = authorById.get(Number(s.userId));
+					return {
+						id: s.id,
+						userId: s.userId,
+						username: author?.username ?? null,
+						look: author?.look ?? null,
+						message: s.message,
+						createdAt: s.createdAt,
+					};
+				});
+			},
+		);
 
 		return apiJson({ shouts: data });
 	} catch {