Adds product interaction data to leads

Closes #354269 (closed), and is part of https://gitlab.com/gitlab-com-top-initiatives/free-saas-user-efficiency/free-saas/-/issues/26#net-new-fields-for-trial-users

Closes #361458 (closed), as it addresses a flakey spec.

This value can be defaulted downstream (and also for trials), but we try to address a couple concerns by always specifying them.

This adds the new SaaS Registration interaction type, but also attempts to make it clear (inside gitlab) where each one is coming from. This is cleaner and hopefully more clear over time than adding more endpoints in the customers applicatiuon, or trying to rename the create_hand_raise_pql endpoint at this time -- but we'd recommend the rename of that action in a follow up issue to this one.