Coupon Reward Fixed Price Order Line Link

This is a technical bridge module with no new screens or menus. It connects two existing promotion features: the one that tracks promotions on sales order lines and the one that applies a fixed-price discount as a reward.

When Odoo applies a fixed-price reward from a coupon program to a sales order, the module automatically writes the promotion program onto the affected sales order lines. This means each line that received the fixed-price discount is stamped with the coupon program that produced it.

• It extends the sale.order model.
• It hooks into the reward calculation step that sets fixed-price rewards for order lines.
• After the parent logic returns the affected lines, it stores the program reference on those lines.
• No new fields, views, menus, reports, emails or scheduled actions are added by this module.

The practical effect is traceability: users and downstream features can see which promotion program is behind a discounted line, which matters when several promotions exist or when reporting on promotions. Because it only adds a link between existing mechanisms, it does not change prices, taxes or discount amounts by itself.