[18.0][MIG] product_sale_price_from_pricelist: Port to Odoo 18.0

- Update manifest version to 18.0.1.0.0
- Update view inheritance to use Odoo 18 <block>/<setting> structure
- Update pricelist models for Odoo 18 API changes (qty parameter)
- Remove required=True from company_dependent field
- Add comprehensive test suite (33 tests)
- Tests cover: pricelist calculations, stock moves, product templates, and config settings

product_sale_price_from_pricelist/models/product_template.py

@@ -42,7 +42,6 @@ class ProductTemplate(models.Model):
         '* Triple discount: take into account all discounts when updating the last purchase price. Needs "Purchase Triple Discount" OCA module.\n'
         "* Manual update: Select this for manual configuration of cost and sale price. The sales price will not be calculated automatically.",
         default="without_discounts",
-        required=True,
         company_dependent=True,
     )