Stock - Reception screen (Subcontract Productions integration)

This module is an automatic bridge between the Reception screen and subcontracted production. It changes how the reception screen behaves when the goods being received come from a subcontractor.

• When a user splits a reception line for a subcontracted product, the link to the original production move is preserved, so the split does not break the subcontracting flow.
• When validating a subcontracted move, the related transfer is re-assigned automatically if it is not cancelled or done.
• When finishing a subcontracted move, backorders are not created, so the reception is completed in one step.
• When finishing the whole reception, component moves that are still open are removed for subcontracted products that use tracked components, avoiding leftover lines.
• During production recording, if the finished goods are going to an incoming transfer, that transfer is unreserved before recording and re-assigned afterwards.

The module touches stock.move, stock.move.line, stock.reception.screen and the production recording wizard. It adds no new menus or screens; it only adjusts existing reception and production behaviour.