Sale Promotion Rule Assortment

This module extends the sales promotion rule so that a promotion can be restricted to a specific set of products instead of applying to the whole order.

On the promotion rule form, a new 'Filter' field lets you choose a product assortment. Only filters marked as assortments can be selected. If you leave it empty, the promotion keeps working on all products as before.

When a filter is set, the promotion only considers order lines whose product matches the filter. Lines with other products are ignored for the promotion and are excluded from the total amount used to evaluate the rule. This means a discount or gift rule can be limited to, for example, only consumable products.

• The promotion rule screen gains a Filter field next to the restricted partners field.
• The rule's product scope is computed from the selected filter's domain.
• Order lines outside the assortment are removed from the amount used by the rule.
• A new restriction type 'product_assortment' is added to the rule's restriction list.

The module touches sale.promotion.rule and relies on product assortments stored as filters on product.product. It does not add its own menus; the new option appears inside the existing promotion rule form.