Is it possible to make an extension that specifically deals with the Form view, namely to add new form field types? I'm looking to try and make a linked record field that allows you to create new linked records, but everything in the Blocks SDK API mostly seems to revolve around manipulating the base itself, or making an extension-only view of a base's data.
Is this not possible? Is something like miniExtensions just building a whole new form view from scratch? (Note: I have looked at Fillout, but I'm mildly concerned about data privacy and would like to see if it's feasible through extensions alone.)