Improved compatibility of the cart override with PrestaShop versions where the `CartCore::getOrderTotal()` method includes an additional `$keepOrderPrices` parameter.
Updated the cart total calculation logic to avoid applying Promotion PRO custom discount processing in Back Office contexts where it is not needed.
Improved the `getProducts()` and `updateQty()` override logic to prevent gift product and promotion rules from interfering with Back Office cart creation or cart quantity updates.
