Inbound Tracking Number Missing on Bulk Orders

When we place a bulk order with Daklapack (more than one kit in a shipment), our system does not store the inbound tracking number that Daklapack's API returns. I've confirmed that their API is exposing the data, so it's an update we need to make on our side.

No files, tests, or entry points are named. Start by tracing the Daklapack API integration and bulk-order handling to where inbound shipment data is persisted; confirm the API response field and verify that bulk orders retain the inbound tracking number, adding or updating coverage if the existing test structure shows where it belongs.

Written by the indexing model from the issue text.