fix: remove unused roles variable, lint and format

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

packages/backend/src/graphql/resolvers/articles.ts

@@ -1,7 +1,20 @@
 import { builder } from "../builder";
 import { ArticleType, ArticleListType, AdminArticleListType } from "../types/index";
 import { articles, users } from "../../db/schema/index";
-import { eq, and, lte, desc, asc, ilike, or, count, arrayContains, isNotNull, ne, type SQL } from "drizzle-orm";
+import {
+  eq,
+  and,
+  lte,
+  desc,
+  asc,
+  ilike,
+  or,
+  count,
+  arrayContains,
+  isNotNull,
+  ne,
+  type SQL,
+} from "drizzle-orm";
 import { requireAdmin } from "../../lib/acl";
 import type { DB } from "../../db/connection";