Refactor `partner` cookie into an JWT context

[rafek1241]

Example: https://jasonwatmore.com/post/2019/10/11/aspnet-core-3-jwt-authentication-tutorial-with-example-api
I can use OAuth and typical authentication because it could be more suitable for such requirements instead of the cookie feature.
partner is request-specific information that should be changed depends on the client who is requesting that action.