Exposing recordedKeys for rendering active key states

[lewisl9029]

Hey Johannes, really appreciate your work on the library, been using it as part of a new hotkeys system and really enjoying it so far! :)

One thing I wanted to do is render the hotkeys in an active state as they're pressed in part of a sequence to give users some visual feedback. Here's what this might look like in practice:

I don't think this is possible with the current version of the library, but I did come up with a fairly small changeset that enables it, by turning recordedKeys into React state and exposing it as part of the hook output. I have it in a WIP branch here that I've published to https://www.npmjs.com/package/@lewisl9029/react-hotkeys-hook if anyone wants to give it a shot.

A few notes on the implementation:

• I've gated this feature behind an option exposeRecordedKeys, both for backwards compatibility, and for performance, since enabling this would cause rerendering whenever recordedKeys updates, which could result in perf regressions.
• This would still be a breaking change since we now return more than just the ref from the payload (I've made it return an object of the shape { scopeRef, recordedKeys }). So will need a major version bump.

Would you be interested in a PR to integrate this into the library? Would be more than happy to upstream it and help update the docs and whatnot. But also would be happy to keep it in my fork for now if you don't think it belongs here.

Cheers!