Polish admin hub pages: drop duplicate headers, align CTAs and empties.

Remove redundant titles under AdminHubChrome, style events/polls create flows with admin chrome + i18n, and standardize empty states / teams form classes.

Co-authored-by: Cursor <[email protected]>

src/app/admin/articles/page.tsx

@@ -53,17 +53,9 @@ export default async function AdminArticles({
 
 	return (
 		<main>
-			<div className="flex items-center justify-between mb-6">
-				<div>
-					<h1 className="m-0 text-2xl font-extrabold text-[var(--admin-text)]">
-						{t("title")}
-					</h1>
-					<p className="m-0 text-sm text-[var(--admin-text-muted)] mt-1">
-						{t("subtitle")}
-					</p>
-				</div>
+			<div className="flex justify-end mb-6">
 				<Link href="/admin/articles/new" className="btn btn-primary">
-					+ {t("newArticle")}
+					{t("newArticle")}
 				</Link>
 			</div>