Add React 19 peer dependency

[slorber]

Add React 19 in peer dependencies

Fix #34

According to #34 (comment) all the people that tried React 19 with this lib reported no problem.

I took a look at the code and couldn't find any code that would be problematic for React 19 (defaultProps, forwardRef...) so it should be relatively safe to allow React 19 (and you can still revert if needed)

Docusaurus v3.7 is running on React 19 and our debug plugin uses this lib already in production for months, and for some of our users.

https://docusaurus.io/__docusaurus/debug

[tats-u]

It might be better to upgrade react, react-dom, and @types/react in devDependencies, too. (Possibly other devDependencies might be incompatible with them though)

[slorber]

I'd prefer to keep the PR minimal so that it's easy to review/merge/publish asap

But yeah upgrading the repo's dependency remains a good idea

[tats-u]

It makes sense. We have only to send another PR if necessary.

[AnyRoad]

I think it might be better to keep react, react-dom, and @types/react in devDependencies as it is too ensure that library is still compatible with React 18.