These styles aren't great, but they're hopefully
better than none at all and inspire a follow up
commit from somebody else (so it starts to look
like a "real" feature instead of feeling completely
proof-of-concept).
A "zform" knows how to render data that follows our
schema for widget messages with form elements like
buttons and choices.
This code won't be triggered until a subsequent
server-side commit takes widget_content from
API callers such as the trivial chat bot and
creates submessages for us.
Steve Howell