Add player leaderboard and homepage preview

lib/leaderboard.ts

@@ -0,0 +1,36 @@
+import "server-only";
+import { admin, required } from "./supabase";
+import type {
+  LeaderboardData,
+  LeaderboardDifficulty,
+} from "@/shared/leaderboard";
+
+export async function leaderboard({
+  difficulty = "all",
+  search = "",
+  page = 1,
+  limit = 25,
+}: {
+  difficulty?: LeaderboardDifficulty;
+  search?: string;
+  page?: number;
+  limit?: number;
+} = {}): Promise<LeaderboardData | null> {
+  try {
+    return required(
+      await admin().rpc("player_leaderboard", {
+        p_difficulty: difficulty,
+        p_search: search,
+        p_page: page,
+        p_limit: limit,
+      }),
+    ) as unknown as LeaderboardData;
+  } catch (error) {
+    // A leaderboard outage must not take the map catalog or homepage offline.
+    console.error(
+      "Leaderboard query failed",
+      error instanceof Error ? error.message : "Unknown error",
+    );
+    return null;
+  }
+}