feat: Users API, ownership transfer and removal of the legacy role string

features/activity-log-producers.feature

@@ -1,4 +1,5 @@
 Feature: Every real action of the back-office is recorded in the activity log from inside its use case
+  Superseded in part by roles_permissions_users_api: user.change_role and user.transfer_ownership (security) join the users category, and invite.create and invite.accept carry the params role_id and role (the role name).
 
   As the owner of a RenewCMS site
   I want articles, media, users and invites, and system tasks to leave an activity event