feat(dashboard): Add Night Mode widget to dashboard

Add a compact Night Mode widget to the main dashboard that allows:
- Quick toggle of night mode on/off
- View countdown to next scheduled action
- Manual start/stop of all services
- See count of running vs stopped services

The widget links to the full night-mode settings page for detailed
configuration.

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

admin-v2/app/(admin)/dashboard/page.tsx

@@ -6,6 +6,7 @@ import { getStoredRole, isCategoryVisibleForRole, RoleId } from '@/lib/roles'
 import { CategoryCard } from '@/components/common/ModuleCard'
 import { InfoNote } from '@/components/common/InfoBox'
 import { ServiceStatus } from '@/components/common/ServiceStatus'
+import { NightModeWidget } from '@/components/dashboard/NightModeWidget'
 import Link from 'next/link'
 
 interface Stats {
@@ -111,7 +112,18 @@ export default function DashboardPage() {
         ))}
       </div>
 
+      {/* Infrastructure & System Status */}
+      <h2 className="text-lg font-semibold text-slate-900 mb-4">Infrastruktur</h2>
+      <div className="grid grid-cols-1 lg:grid-cols-2 gap-6 mb-8">
+        {/* Night Mode Widget */}
+        <NightModeWidget />
+
+        {/* System Status */}
+        <ServiceStatus />
+      </div>
+
       {/* Recent Activity */}
+      <h2 className="text-lg font-semibold text-slate-900 mb-4">Aktivitaet</h2>
       <div className="grid grid-cols-1 lg:grid-cols-2 gap-6">
         {/* Recent DSR */}
         <div className="bg-white rounded-xl border border-slate-200 shadow-sm">
@@ -127,9 +139,6 @@ export default function DashboardPage() {
             </p>
           </div>
         </div>
-
-        {/* System Status */}
-        <ServiceStatus />
       </div>
 
       {/* Info Box */}