fix: export worksheet schema tables from index

Add missing exports for worksheetAttempts and worksheetMastery
tables to fix import errors in API routes.

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Co-Authored-By: Claude <noreply@anthropic.com>

apps/web/src/db/schema/index.ts

@@ -20,3 +20,5 @@ export * from "./room-game-configs";
 export * from "./user-stats";
 export * from "./users";
 export * from "./worksheet-settings";
+export * from "./worksheet-attempts";
+export * from "./worksheet-mastery";