calendar and vehicle booking rework

frontend/src/pages/FahrzeugBuchungen.tsx

@@ -1,4 +1,4 @@
-import React, { useState } from 'react';
+import { useState } from 'react';
 import {
   Box,
   Container,
@@ -46,7 +46,6 @@ import {
 import { useQuery, useMutation, useQueryClient } from '@tanstack/react-query';
 import { useNavigate } from 'react-router-dom';
 import { format, parseISO } from 'date-fns';
-import { de } from 'date-fns/locale';
 import DashboardLayout from '../components/dashboard/DashboardLayout';
 import ChatAwareFab from '../components/shared/ChatAwareFab';
 import { useAuth } from '../contexts/AuthContext';
@@ -54,8 +53,6 @@ import { usePermissionContext } from '../contexts/PermissionContext';
 import { useNotification } from '../contexts/NotificationContext';
 import { bookingApi, fetchVehicles, kategorieApi } from '../services/bookings';
 import type {
-  FahrzeugBuchungListItem,
-  Fahrzeug,
   BuchungsArt,
   BuchungsKategorie,
 } from '../types/booking.types';