fix: resolve lint errors from ACL/admin implementation

- Remove unused requireOwnerOrAdmin import from videos.ts
- Remove unused requireAuth import from users.ts
- Remove unused GraphQLError import from articles.ts
- Replace URLSearchParams with SvelteURLSearchParams in admin users page
- Apply prettier formatting to all changed files

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

CLAUDE.md

@@ -75,14 +75,14 @@ Points + achievements system tracked in `user_points` and `user_stats` tables. L
 
 ## Environment Variables (Backend)
 
-| Variable | Purpose |
-|----------|---------|
-| `DATABASE_URL` | PostgreSQL connection string |
-| `REDIS_URL` | Redis connection string |
-| `COOKIE_SECRET` | Session cookie signing |
-| `CORS_ORIGIN` | Frontend origin URL |
-| `UPLOAD_DIR` | File storage path |
-| `SMTP_HOST/PORT/EMAIL_FROM` | Email (Nodemailer) |
+| Variable                    | Purpose                      |
+| --------------------------- | ---------------------------- |
+| `DATABASE_URL`              | PostgreSQL connection string |
+| `REDIS_URL`                 | Redis connection string      |
+| `COOKIE_SECRET`             | Session cookie signing       |
+| `CORS_ORIGIN`               | Frontend origin URL          |
+| `UPLOAD_DIR`                | File storage path            |
+| `SMTP_HOST/PORT/EMAIL_FROM` | Email (Nodemailer)           |
 
 ## Docker