Fix TypeScript types (retroactively?) / Consider external typing packages

[brokenthorn]

Hello,

First and foremost, this is just a personal suggestion, and I am open to other options if you can provide them, and if not, that is OK too. I just wanted to ask and see what you guys think.

So, we constantly have to fight the provided types from Scheduler Pro and overwrite them, and then forget to check them with every version upgrade, possibly leading to runtime bugs.

In a previous issue #7760, I mentioned one such case, but there are so many others. That ticket was closed and the fix is supposed to be release with v6 alpha, but we cannot wait that long, or do a major version upgrade that easily when it gets out.

Could you possibly consider creating separate @types/* packages for each major/minor version, with patch version to signify new fixes/evolution, allowing these types to be worked on/fixed retroactively, possibly even open them up for outside contribution and PRs?

This would greatly simplify the maintenance of these types, and if Bryntum/you ever have to backport a type fix, you can do it for everyone by just updating the types packages.

This also means that we don't have such a huge maintenance burden by having to check if the latest Scheduler version or whatnot, has provided new types, or fixes for the current overrides each and every one of us has. It's a really tedious and error prone job.

Here are some other examples where lots of types are intersected with any resulting in practically a final type of any.

PS: we would be happy to be first ones to start contributing to these types, provided you can get the ball rolling by exporting the existing types first, into a separate NPM package.