Add the shipping information to the cart object that is retrieved via useApi in Shopify POS UI extensions apps.
Since POS orders typically aren’t shipped you may need to add some custom logic.
You can add shipping address details using cart properties through the addCartProperties
mutation.
Then in the order webhook, you can check for the presence of your custom shipping address cart properties and update the order accordingly.
There is functionality related to shipping in the app on the Checkout screen. You can set what line items will be shipped, you can select the shipping address for the customer, and what shipping method. That is not present on the Cart object
It would be good to at least have a requiresShipping boolean on the line item…