fix(order-wizard): pass selectedCompanyId when creating end customer as admin

shop/components/order-wizard.tsx

@@ -392,7 +392,7 @@ export function OrderWizard({
     if (!newCustomerForm.company_name.trim()) return
     setIsCreatingCustomer(true)
     try {
-      const created = await createEndCustomer(newCustomerForm)
+      const created = await createEndCustomer(newCustomerForm, selectedCompanyId || undefined)
       setEndCustomers(prev => [...prev, created])
       setSelectedEndCustomerId(created.id)
       setCustomerMode('select')
@@ -400,8 +400,8 @@ export function OrderWizard({
         company_name: '', vat_id: '', first_name: '', last_name: '', street: '', zip: '', city: '',
         bank_iban: '', bank_bic: '', bank_name: '', bank_owner: '',
       })
-    } catch (e) {
-      alert('Fehler beim Anlegen des Kunden.')
+    } catch (e: any) {
+      alert(`Fehler beim Anlegen des Kunden: ${e.message || 'Unbekannter Fehler'}`)
     } finally {
       setIsCreatingCustomer(false)
     }