fix: enforce semantic contrast across admin

src/app/admin/articles/new/page.tsx

@@ -21,7 +21,7 @@ export default async function NewArticle({ searchParams }: { searchParams: Promi
           </p>
         </div>
       </div>
-      {error ? <p className="text-xs text-red-600 dark:text-red-400 mb-4">Error: {error}</p> : null}
+      {error ? <p className="text-xs text-[var(--color-error-text-readable)] dark:text-[var(--color-error-text-readable)] mb-4">Error: {error}</p> : null}
       <ArticleForm action={createArticle} />
     </main>
   );