Use product data and scan data to compute the main countries where a product is sold

[stephanegigandet]

I plan to create a new MainCountries module:

Products on Open Food Facts have a countries_tags field that list the countries
where a product is sold. The information is entered by users, food producers,
and additional countries are added by the scanbot.pl script if a product
is scanned by 5 or more different IP addresses in a specific country.

In some cases, products may be marked as sold in a country even it is not widely
sold in that country. For instance, a lot of discount shops import products that
are intended for sale to other countries. Scan data can be tricky as well:
people who live close to a border often shop in another country, and they
may scan products when they are back in their home country.

This module tries to determine which countries a product is "mostly" sold in.

The determination can be made on different factors:

• scan data
• languages
• brands
• etc.

[github-actions]

This issue has been open 90 days with no activity. Can you give it a little love by linking it to a parent issue, adding relevant labels and projets, creating a mockup if applicable, adding code pointers from https://github.com/openfoodfacts/openfoodfacts-server/blob/main/.github/labeler.yml, giving it a priority, editing the original issue to have a more comprehensive description… Thank you very much for your contribution to 🍊 Open Food Facts