fix: enforce semantic contrast across admin

src/app/admin/articles/[id]/page.tsx

@@ -39,7 +39,7 @@ export default async function EditArticle({
           </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={async (fd) => {
           "use server";