[Feature Request] Ability to track if form state has changed since previous submission attempt (setMeta on the form state)

[jzxhuang]

I would like to track if the form state has changed since the previous submission attempt. Example use case:

• show an error banner on submission
• hide the error banner when the user touches any part of the form

It would be ideal if this was exposed as a state variable on the form. Otherwise, we should at least be able to build this ourselves by exposing a setMeta for the form state, as discussed in this Discord thread.

This feature request appears similar to #1144.

Furthermore, I just thought of something: it would likely be useful for this type of state to exist on every single form field, too. This is likely an extension of this request - I would find it most useful to have this state ont he form itself first - but a relevant thought.

Thanks!