**Step to reprocduce :**
1. Install sale_project module
2. Create a product
        - type: Service
        - Invoice policy: based on the milestones
        - Create on order: Project & Task.
3. Create a sale order with that product and add two SO lines with different descriptions.
4. Confirm the sale order.
5. Click on the Tasks smart button in the sale order to open the generated tasks.
6. From one of the tasks (e.g., m1)
7. Manually remove the existing milestone and sales order item from the task.
8. Then assign a different milestone (e.g., m2) to the task.
9. The sale order item set different (e.g., m1) instead of the newly set milestone.

**Issue:**

When a task has its `milestone_id` and `sale_line_id` manually cleared, and a new milestone
is later assigned, the task does not get the correct Sales Order Item.

**Cause:**
In the `_compute_sale_line` method, the logic priority the parent task and project when
computing the `sale_line_id`, and only uses the `milestone_id.sale_line_id` as a fallback.

https://github.com/odoo/odoo/blob/259f7eafb15882807640a00cf6939129f27c8fbb/addons/sale_project/models/project_task.py#L109-L113

**Solution :** 

To fix this `_compute_sale_line` method to priority the milestone's `sale_line_id` 
when a milestone is explicitly set. This ensures that if the task’s milestone 
changes, its sale line reflects the one from the milestone, even for subtasks.

opw-4701106

Forward-Port-Of: odoo/odoo#215213

**Step to Reproduce:**
1. Install `sale_loyalty` and `sale`
2. Enable the `Pricelists` option in the settings.
3. Create a pricelist named demo.
4. Create a Discount & Loyalty named `test program` with type `Discount Code`,
5. Assign the demo pricelist to the loyalty program.
6. Copy the discount code from the program’s conditional rules.
7. Archive the demo pricelist.
8. create sale order for any product.
9. Try to apply the copied coupon code.

**Observation:**
- An error is shown: "This code is invalid".
- check loyalty program `test program` pricelist field is empty, that suggesting it's valid for all pricelists, but the coupon still fails.

**Issue:**
- When a linked pricelist is archived, it's hidden in the UI, but the relation still exists in the relational table.
```17_sale=# select id,name,active from product_pricelist;
 id |                name                | active 
----+------------------------------------+--------
  1 | {"en_US": "Default USD pricelist"} | t
  2 | {"en_US": "new"}                   | f
(2 rows)

17_sale=# select * from loyalty_program_product_pricelist_rel;
 loyalty_program_id | product_pricelist_id 
--------------------+----------------------
                  5 |                    2
(1 row)
```
- While filtering the domain for coupon, the condition is not satisfied due to the program's pricelist.

https://github.com/odoo/odoo/blob/94d727bd9ba38116d3e14188c730c7566744e9f0/addons/sale_loyalty/models/sale_order.py#L636-L647

**Solution:**
- Display a validation error to the user when trying to archive a pricelist
  that is linked to any active promotional programs.

opw-4841678



---
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Forward-Port-Of: odoo/odoo#214968