Fix: remove inventory quantity from invoice display

- Removed Quantity column from invoice item listing
- Removed inventory stock quantity values from invoice output
- Display only item name and price in generated invoices

Fixes #2115

Trenser.VehicleServiceSystem/Trenser.VehicleServiceSystem/views/MenuHelper.h

@@ -597,7 +597,6 @@ inline void displayInvoices(util::Map<std::string, const Invoice*> currentUserIn
                 std::cout << "\nItems Used:\n";
                 std::cout << std::left
                     << std::setw(20) << "ItemName"
-                    << std::setw(10) << "Quantity"
                     << std::setw(10) << "Price"
                     << std::endl;
                 std::cout << std::string(40, '-') << std::endl;
@@ -606,7 +605,6 @@ inline void displayInvoices(util::Map<std::string, const Invoice*> currentUserIn
                     InventoryItem* currentItem = inventoryItemsInInvoice.getValueAt(iterator);
                     std::cout << std::left
                         << std::setw(20) << currentItem->getPartName()
-                        << std::setw(10) << currentItem->getQuantity()
                         << std::setw(10) << currentItem->getPrice()
                         << std::endl;
                 }