Lifetime package - automatic user creation and email send

We're going to go with the solution for listening to stripe webhook for lifetime product and create the user automatically. Email wise, we can fire a PostHog event and you can trigger an email for this usecase. They won't need any magic links, because the user will also get created in clerk, so they will just need to go to app.getformflow.io and login, either with google directly or via email and they receive the login code.