code: public function onContentChange(ResourceEventInterface $event)
      {
          $sale = $this->getSaleFromEvent($event);
  
          if ($this->persistenceHelper->isScheduledForRemove($sale)) {
              $event->stopPropagation();
  
              return;
          }
  
          $this->handleContentChange($sale);
  
          // Reflect content change on update timestamp
          $sale->setUpdatedAt(new\DateTime());
  
          $this->persistenceHelper->persistAndRecompute($sale, false);
      }
docs: Content (item/adjustment/payment/shipment/invoice) change event handler.
  
  @param ResourceEventInterface $event
  
  @throws \Ekyna\Component\Commerce\Exception\CommerceExceptionInterface