From a sellers perspective the items in a buyers shopping cart are seen as progress toward an order. Often when someone looks into a shopping cart a sample 'order' is prepared for the customer, encouraging them to look at that prepared-order and complete the purchase.
Of course, usually an 'order', without qualification, is known to be a completed order.
.. the yet to be completed, potential order made of of the items in the card might be called -- (using my wording, not claiming these are industry jargon):
In the comments to a comment I made before turning this into an answer he read work order however I am not sure that is right, because in many industries I have heard work order to mean a completed service based order (more like at a mechanic shop or repair visit, or an internal custom fabrication that needs to be performed as it has been confirmed and paid for)
After purchase but in the process of fulfilling the order for a customer:
If this were an order confirmed by customer but in the process of being filled other terms like 'order-crate' (like a basket in a warehouse being filled but not yet packed ?) or maybe a "order-in-progress" might work.
@Phil_Sweet , in a comment, mentions an industry term 'pick bin' which sounds like it might be the industry term for items being aggregated in a warehouse off the list of items on a completed order, prior to packing and delivery.