Track partner pricelist changes

This module makes the pricelist assigned to a contact traceable. In Odoo, a partner's pricelist can change automatically when the country or state of the contact is updated, and the user may not notice it. With this module, each change to the pricelist field on res.partner is recorded in the contact's chatter, showing the old value, the new value, the user and the date.

• The tracked field is the pricelist field on the contact form (property_product_pricelist).
• Changes are logged automatically, whether they come from a manual edit or from an automatic reassignment triggered by another change on the contact.
• The history appears in the same place as other tracked fields: the log notes / chatter of the contact record.

No new menus, buttons, reports or scheduled jobs are added. The module only extends the existing contact model and relies on Odoo's standard tracking mechanism. It depends on the product module, which provides pricelists.