Customers need a way to view full packing slip details on screen without printing or downloading a PDF.

The order view/shipping label does not always show enough item quantity detail for accurate packing, especially for products with variants or multiple pack quantities. This means packers may need to print/download packing slips just to confirm what to pack, which slows fulfilment and creates unnecessary paper waste.

Requested behaviour:

Add a Preview Packing Slip or View Packing Slip action beside Print Packing Slip so users can quickly view full item details and quantities from the order screen.