feat(notifications): add per-tenant notification preferences

frontend/pages/settings/index.vue

@@ -6,6 +6,8 @@ const router = useRouter()
 
 const items = [{
   label: 'Profil',
+},{
+  label: 'Benachrichtigungen',
 },{
   label: 'Projekte',
   content: 'This is the content shown for Tab1'
@@ -57,6 +59,7 @@ const isLight = computed({
           </InputGroup>
 
         </div>
+        <NotificationPreferences v-else-if="item.label === 'Benachrichtigungen'" />
         <div v-else-if="item.label === 'Projekte'">
           <USeparator
             label="Phasenvorlagen"