feat: add campaign configuration controls

app/dashboard/campaigns/page.tsx

@@ -1,10 +1,11 @@
-import { DashboardPlaceholderPage } from "@/components/dashboard-placeholder-page";
+import { CampaignsBoard } from "@/components/campaigns/campaigns-board";
 
 export default function CampaignsPage() {
   return (
-    <DashboardPlaceholderPage
-      description="Kampagnen-Konfiguration, PLZ, Radius, Limits und Laufplanung folgen in TASK-5."
-      title="Kampagnen"
-    />
+    <main className="px-4 py-5 sm:px-6 lg:px-8">
+      <div className="mx-auto flex w-full max-w-7xl flex-col gap-6">
+        <CampaignsBoard />
+      </div>
+    </main>
   );
 }