complete new audit system

frontend/src/pages/contracts/ContractForm.tsx

@@ -9,6 +9,7 @@ import Button from '../../components/ui/Button';
 import Input from '../../components/ui/Input';
 import Select from '../../components/ui/Select';
 import type { ContractType } from '../../types';
+import { formatDate } from '../../utils/dateFormat';
 import { Plus, Trash2, Eye, EyeOff, Info, X, ArrowLeft } from 'lucide-react';
 
 // Contract types are now loaded dynamically from the database
@@ -724,7 +725,7 @@ export default function ContractForm() {
                 {...register('previousContractId')}
                 options={predecessorContracts.map((c) => ({
                   value: c.id,
-                  label: `${c.contractNumber} (${c.type}${c.startDate ? ` - ${new Date(c.startDate).toLocaleDateString('de-DE')}` : ''})`,
+                  label: `${c.contractNumber} (${c.type}${c.startDate ? ` - ${formatDate(c.startDate)}` : ''})`,
                 }))}
                 placeholder="Keinen Vorgänger auswählen"
               />