fix(accidentForm): prevent reactivity issues by creating a new sorted array

- Modified the sorting logic in AccidentFormDialog to create a new array from the filtered members, addressing potential reactivity problems during sorting.

frontend/src/components/AccidentFormDialog.vue

@@ -108,7 +108,8 @@ export default {
       console.log('[AccidentFormDialog] filtered.length:', filtered.length);
       
       // Alphabetisch sortieren nach Nachname, dann Vorname
-      const sorted = filtered.sort((a, b) => {
+      // Erstelle ein neues Array, um Reaktivitätsprobleme zu vermeiden
+      const sorted = [...filtered].sort((a, b) => {
         const lastNameA = (a.lastName || '').toLowerCase();
         const lastNameB = (b.lastName || '').toLowerCase();
         if (lastNameA !== lastNameB) {