Refactor ESLint configuration and update code formatting: Standardize quotes in eslint.config.mjs, next.config.js, and various TypeScript files for consistency. Add Prettier as a dependency and include formatting scripts in package.json. Clean up unnecessary whitespace in multiple files to enhance code readability.

app/api/admin/preferences/route.ts

@@ -53,21 +53,21 @@ export async function PUT(request: Request) {
       where: { id: "global" },
       update: {
         homeBackground:
-          homeBackground === "" ? null : homeBackground ?? undefined,
+          homeBackground === "" ? null : (homeBackground ?? undefined),
         eventsBackground:
-          eventsBackground === "" ? null : eventsBackground ?? undefined,
+          eventsBackground === "" ? null : (eventsBackground ?? undefined),
         leaderboardBackground:
           leaderboardBackground === ""
             ? null
-            : leaderboardBackground ?? undefined,
+            : (leaderboardBackground ?? undefined),
       },
       create: {
         id: "global",
-        homeBackground: homeBackground === "" ? null : homeBackground ?? null,
+        homeBackground: homeBackground === "" ? null : (homeBackground ?? null),
         eventsBackground:
-          eventsBackground === "" ? null : eventsBackground ?? null,
+          eventsBackground === "" ? null : (eventsBackground ?? null),
         leaderboardBackground:
-          leaderboardBackground === "" ? null : leaderboardBackground ?? null,
+          leaderboardBackground === "" ? null : (leaderboardBackground ?? null),
       },
     });