Before this PR, Setting the on-hand quantity from the product form 
would correctly set the product's quantity but also reset the inventory
quantity to 0. While this behavior is correct,it caused a line decoration 
warning to appear in the Inventory Adjustment tree view.

Steps to Reproduce
===================
- Create a storable, non-tracked product.
- Update its quantity by clicking the "Update Quantity" button, ensuring 
  multi-location is disabled.
- Go to Inventory Adjustment and locate the newly created product. 
  The inventory quantity is correctly set to 0, but it is highlighted with a warning.

Issue
======
Although the inventory quantity is correctly set to 0, the `inventory quantity set` 
field is not reverted, causing the line decoration warning to appear.

This commit resolves the issue by using an existing method that clears the 
inventory quantity and sets the `inventory quantity set` field to false.


task: [4579053](https://www.odoo.com/odoo/my-tasks/4579053)

Forward-Port-Of: odoo/odoo#199598

When the warehouse is set to pbm_sam, MOs are assigned the procurement group name if the move origin differs from the group_id. This causes a validation error when confirming a sales order with a client_order_ref, as MO references must be unique per company.

For example, if an SO has a reference S00011 - test_client_order_ref, it differs from S00011, leading to an MO name conflict. This fix ensures that MO names are always generated using the picking type sequence instead of inheriting the procurement group name, preventing duplicate references or incorrectly setting the MO name as the SO name.

Current behavior before PR:
If there is more than one sale order line with MTO products:
We get a duplicate name error

If there is one sale order line with an MTO product:
We get a MO.name == SO.name

Desired behavior after PR is merged:
Both cases are resolved and the MO(s) are successfully created with the appropriate name

Steps to reproduce:
1.) Install sales; inventory; manufacturing
2.) Enable multi-step routes
3.) Unarchive MTO
4.) Set warehouse manufacture steps to:
Pick components, manufacture, then store products (3 steps)
(manufacture_steps == 'pbm_sam')
5.) Unarchive MTO
6.) Create two storable products (enable manufacture and mto routes)
7.) Create an SO with both products
8.) Add any text to the Customer Reference on the sales order (client_order_ref)
9.) Try to confirm the SO

Validation Error
The operation cannot be completed: Reference must be unique per Company!

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Forward-Port-Of: odoo/odoo#203823