Lock Done Quantity Changes in Stock Moves

This module adds an option in Inventory settings called "Limit Updates to Done Quantity After Validation". When enabled for a company, the done quantity of a stock move line that is already in the done state can no longer be edited by ordinary users.

• The setting is stored per company and can be turned on or off from the Inventory configuration screen.
• A new user group, "Inventory: Edit done quantity of done stock moves", is created. Only users in this group are allowed to change the done quantity after validation.
• If a user without this group tries to change the done quantity on a validated move, Odoo blocks the change and shows an error message.
• If the move line is locked, even users with the group cannot change the done quantity until the move is unlocked, and an error explains this.
• The rule only applies when the company setting is active and the move line is already done; otherwise editing behaves as before.

The module touches the stock move line model, the company settings, and the Inventory settings screen. It does not add new menus or reports.