feat: show upcoming assignments of teamers for administrative users

closes #869b9vkp4

src/Menu/AdminMenuBuilder.php

@@ -317,6 +317,13 @@ class AdminMenuBuilder extends AbstractMenuBuilder
                 'title' => 'Vergangene Einsätze',
             ],
         ]);
+        $menu->addChild('Bevorstehende Einsätze', [
+            'route' => 'app_administrative_teamer_upcoming_assignments',
+            'routeParameters' => $this->getDefaultRouteParameters('uuid'),
+            'linkAttributes' => [
+                'title' => 'Bevorstehende Einsätze',
+            ],
+        ]);
         $menu->addChild('Anmerkungen (intern)', [
             'route' => 'app_admin_teamer_remarks_internal',
             'routeParameters' => $this->getDefaultRouteParameters('uuid'),