fix(admin): repair layout and character artwork

app/admin/page.tsx

@@ -2,6 +2,7 @@ import { redirect } from "next/navigation";
 import { connection } from "next/server";
 
 import { StructuredDashboard } from "@/components/admin/structured-dashboard";
+import { AdminHeader } from "@/components/admin/admin-header";
 import { getAdminSession } from "@/lib/auth/server";
 import { getActiveCatalog, getLatestCatalogSyncJob, listGuideCards } from "@/lib/guides/queries";
 
@@ -15,9 +16,16 @@ export default async function AdminPage() {
     getActiveCatalog(),
   ]);
   return (
-    <main className="mx-auto flex w-full max-w-7xl flex-col gap-8 p-4 sm:p-6 lg:p-8">
-      <header><p className="text-sm font-medium text-primary">Buzz Sheet Admin</p><h1 className="font-heading text-3xl font-semibold">Guide Dashboard</h1><p className="mt-2 text-muted-foreground">จัดการ Guide แบบภาพ-first และบันทึกขึ้นเว็บไซต์ทันที</p></header>
-      <StructuredDashboard guides={guides} trash={trash} syncJob={syncJob} catalogVersion={catalog?.version ?? null} />
-    </main>
+    <div className="min-h-svh">
+      <AdminHeader />
+      <main className="mx-auto flex w-full max-w-7xl flex-col gap-8 p-4 sm:p-6 lg:p-8">
+        <header>
+          <p className="text-sm font-medium text-primary">Content workspace</p>
+          <h1 className="font-heading text-3xl font-semibold">Guide Dashboard</h1>
+          <p className="mt-2 text-muted-foreground">จัดการ Guide แบบภาพ-first และบันทึกขึ้นเว็บไซต์ทันที</p>
+        </header>
+        <StructuredDashboard guides={guides} trash={trash} syncJob={syncJob} catalogVersion={catalog?.version ?? null} />
+      </main>
+    </div>
   );
 }