Sale Order Country Allowed Product

This module adds a 'Sale Allowed Countries' field on product templates, visible in the Sales tab under 'Country Availability'. If left empty, the product is available everywhere. When a sales order is created, the system checks each order line against the shipping address country. If a product is not allowed in that country, a warning message appears at the top of the sales order form listing the unavailable products.

Users cannot confirm a sales order if any line contains a product not allowed in the shipping country. A validation error blocks confirmation. However, users in the 'Ignore products sale countries' group can bypass this restriction and confirm such orders.

When selecting products in sales order lines, the product list is automatically filtered to show only products allowed in the shipping country. This filtering applies to both the product field and the product template field in order lines. The restriction is based on the shipping address country, not the customer's country.

The module extends product.template, sale.order, and sale.order.line models. It adds a computed boolean field country_available on order lines and a computed HTML message on sales orders. The product search is modified to apply the country filter when the context indicates restriction is needed.