Add sick routes to backend and frontend; update routing and UI components for sickness tracking

frontend/src/composables/useModal.js

@@ -26,6 +26,7 @@ export function useModal() {
   }
 
   const confirm = (message, title = 'Bestätigung') => {
+    console.log('DEBUG useModal.confirm called:', { message, title })
     return new Promise((resolve) => {
       modalConfig.value = {
         title,
@@ -34,7 +35,9 @@ export function useModal() {
         confirmText: 'Ja',
         cancelText: 'Abbrechen'
       }
+      console.log('DEBUG useModal: setting showModal to true')
       showModal.value = true
+      console.log('DEBUG useModal: showModal.value =', showModal.value)
       resolvePromise.value = resolve
     })
   }