fix void

lib/application/void/void_form/void_form_bloc.dart

@@ -1,4 +1,5 @@
 import 'package:bloc/bloc.dart';
+import 'package:collection/collection.dart';
 import 'package:dartz/dartz.dart' hide Order;
 import 'package:freezed_annotation/freezed_annotation.dart';
 import 'package:injectable/injectable.dart' hide Order;
@@ -49,9 +50,10 @@ class VoidFormBloc extends Bloc<VoidFormEvent, VoidFormState> {
         // Recalculate total price
         int newTotal = 0;
         for (var entry in newQuantities.entries) {
-          final item = state.pendingItems.firstWhere(
+          final item = state.pendingItems.firstWhereOrNull(
             (item) => item.id == entry.key,
           );
+          if (item == null) continue;
           newTotal += item.unitPrice.toInt() * entry.value;
         }
 
@@ -71,10 +73,12 @@ class VoidFormBloc extends Bloc<VoidFormEvent, VoidFormState> {
 
         if (state.voidType.isItem) {
           state.selectedItemQuantities.forEach((itemId, voidQty) {
-            final originalItem = state.order.orderItems.firstWhere(
+            final originalItem = state.order.orderItems.firstWhereOrNull(
               (item) => item.id == itemId,
             );
 
+            if (originalItem == null) return;
+
             voidItems.add(
               OrderItem(
                 id: originalItem.id,