Stock Release Channel Propagate Channel Picking

This module extends the release channel feature of the warehouse management app. It adds a new checkbox called "Propagate the release channel to pickings chain" on the operation type configuration screen (the same screen where you set the sequence code for a type of transfer).

When this option is enabled on the operation type of a transfer, and that transfer is released, Odoo looks at the chain of origin moves behind each move and copies the release channel of the released transfer onto the earlier transfers in that chain. In practice, the internal transfers that fed the outgoing transfer receive the same release channel.

The update is done per channel, so all concerned transfers are grouped and updated together. The propagation only happens for operation types where the new checkbox is ticked; otherwise nothing changes.

It touches the stock move and stock picking type models, and writes on stock pickings. No new menus, reports, emails or scheduled actions are added.