fix: fix potential issues with trivia command

shared/modules/trivia/trivia.service.ts

@@ -1,5 +1,5 @@
 import { users, userTimers, transactions } from "@db/schema";
-import { eq, and } from "drizzle-orm";
+import { eq, and, sql } from "drizzle-orm";
 import { config } from "@shared/lib/config";
 import { withTransaction } from "@/lib/db";
 import type { Transaction } from "@shared/lib/types";
@@ -171,7 +171,7 @@ class TriviaService {
             // Deduct entry fee (SINK MECHANISM)
             await tx.update(users)
                 .set({
-                    balance: (user.balance ?? 0n) - entryFee,
+                    balance: sql`${users.balance} - ${entryFee}`,
                 })
                 .where(eq(users.id, BigInt(userId)));