[keycloak-user] Custom entity mapping to User entity

Hello! We are currently looking for an authentication/authorization/access management provider to use for our applications and we happily stumbled upon Keycloak. As of this moment we are looking into if Keycloak fits all of our requirements and if it doesn't how we can modify it to fit our needs. So; we need to add our own entities to Keycloak (which we've seen is possible) but we also have to map some of these entities to the already existing User entity and in the end, have it included inside the ID token. If this is possible, could you maybe give us a short description of how to do this, that would be much appreciated Best Regards Fabian Eriksson