Carriers post the shipping label and (for international) the commercial invoice
to the delivery order's chatter, where they were hard to find. Add two smart
buttons on the stock.picking form that open the latest of each via the PDF
preview dialog (fusion_pdf_preview when installed, else open in a new tab).
Document discovery is carrier-agnostic (computed from the picking's attachments):
labels match 'Label*'; invoices match '*CommercialInvoice*' (UPS/Canada Post) or
'ShippingDoc-*' (FedEx/DHL, _get_delivery_doc_prefix). Buttons hide when absent.
Verified on entech: real FedEx picking resolved its label (invoice correctly
none for a domestic ship); synthetic UPS names resolved label+invoice and the
invoice button fired fusion_pdf_preview.open_attachment.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
423f288507