[Proposal] Add Button knob

[rayliverified]

I'm running into a few situations where I need a button knob that executes a function on press. Specifically, for state transitions and transient states such as animations.

Having a button knob would allow me to trigger and test animations and state transitions, among other functionality.

I'm willing to make a PR if you'd be willing to accept a button knob.

[ookami-kb]

Hi, yeah, looks like a useful feature.

But please wait for some time, I'm currently working on a new version that will bring some breaking changes.

[rayliverified]

KK, sounds good!