Parent External Tracking Number Scan Support for Split Items (Pick & Load)

When cargo is partially released, and an item is split, the unique External Tracking Number remains on the parent, so scanning that barcode during picking doesn’t currently match the child lines on the task.
Implement an enhancement that lets the app recognize the parent External Tracking Number barcode and resolve it to the eligible child line(s) included in the task, enabling scan‑to‑pick without duplicating tracking numbers; if multiple child lines qualify, prompt for disambiguation based on task context.