feat(role): add 'verwaltung' role with gated access to settings and tools

shop/app/admin/settings/page.tsx

@@ -1,7 +1,9 @@
 "use client";
-// Admin Settings page – view & edit SMTP configuration and send test email
+
 import { useEffect, useState } from 'react';
 import { useRouter } from 'next/navigation';
+import { createClient } from '@/lib/supabase/client';
+import { Loader2 } from 'lucide-react';
 
 interface Settings {
   host: string;
@@ -17,17 +19,36 @@ export default function SettingsPage() {
   const [message, setMessage] = useState('');
   const router = useRouter();
 
-  // Load current settings
+  // Load current settings and verify access
   useEffect(() => {
-    fetch('/api/admin/smtp-settings')
-      .then((res) => res.json())
-      .then((data) => {
-        if (data.settings) setSettings(data.settings as Settings);
-        else setMessage('Failed to load settings');
-      })
-      .catch(() => setMessage('Failed to load settings'))
-      .finally(() => setLoading(false));
-  }, []);
+    async function checkAccessAndLoad() {
+      const supabase = createClient();
+      const { data: { user } } = await supabase.auth.getUser();
+      if (!user) {
+        router.push('/auth/login');
+        return;
+      }
+      const { data: userData } = await supabase
+        .from('users')
+        .select('role')
+        .eq('id', user.id)
+        .single();
+      if (!userData || userData.role === 'verwaltung') {
+        router.push('/admin');
+        return;
+      }
+
+      fetch('/api/admin/smtp-settings')
+        .then((res) => res.json())
+        .then((data) => {
+          if (data.settings) setSettings(data.settings as Settings);
+          else setMessage('Failed to load settings');
+        })
+        .catch(() => setMessage('Failed to load settings'))
+        .finally(() => setLoading(false));
+    }
+    checkAccessAndLoad();
+  }, [router]);
 
   const handleChange = (e: React.ChangeEvent<HTMLInputElement>) => {
     const { name, value, type, checked } = e.target;
@@ -69,7 +90,7 @@ export default function SettingsPage() {
     else setMessage(data.error || 'Failed to send test email');
   };
 
-  if (loading) return <div className="p-8">Loading…</div>;
+  if (loading) return <div className="p-8 text-white flex justify-center items-center"><Loader2 className="w-8 h-8 animate-spin text-primary" /></div>;
 
   return (
     <div className="max-w-2xl mx-auto p-8 bg-black/30 backdrop-blur-xl rounded-lg text-white">