🌟No Configurable field validation for checkout questions

[wh0th3h3llam1]

Is your feature request related to a problem? Please describe.
During checkout, we can add custom questions—great!—but those fields don’t have real validation beyond “required”. If I want to have all the emails to end with @xyz.com so that only people at a specific organization can book the ticket or if I want a field to have exactly 9 digit numbers (e.g. student ID), that isn't possible currently.

Describe the solution you'd like

1. A few common validators -> required, email, URL, number only, date, regex
2. Constraints: min/max length for text, numeric ranges, date windows

Additional context

Screenshot of the page where this could be implemented

[daveearley]

Thanks for the suggestion, @wh0th3h3llam1!