feat(events): restore responsive appointment overview and creation

frontend/components/MainNav.vue

@@ -38,6 +38,12 @@ const isRouteActive = (to) => {
 
 const links = computed(() => {
   const organisationChildren = [
+    has("events") && featureEnabled("calendar") ? {
+      label: "Termine",
+      to: "/events",
+      icon: "i-heroicons-calendar-days",
+      active: route.path.startsWith("/standardEntity/events")
+    } : null,
     has("tasks") && featureEnabled("tasks") ? {
       label: "Aufgaben",
       to: "/tasks",