feat: added cjs support via esbuild

[titanism]

@LinusU we have added CJS support without breaking anything or making any drastic changes. can you please merge and publish a new rc? thank you! 🙏 🙇

[LinusU]

Sorry for the late reply on this one.

As this change is right now, it will bundle all of our dependencies into the published package. Whilst still keeping this as dependencies.

I think that bundling dependencies isn't a good way to go, since the end user then might end up with multiple copies of the same module. It would also add an additional maintanence burden on us since we would need to cut new releases anytime a dependency is updated.

Even worse, it could also block users from getting upstream security patches, as we would need to cut a new release with that package upgraded before they could use it. This is in contrast to how it is now where they could simply do npm audit fix or npm update affected-package.

[titanism]

This would only affect CJS users, and I think that is a risk worth taking to at least give them support to be able to use this in CJS... We would gladly help be a maintainer to push out security updates as necessary. Thanks, let us know @LinusU!

[bjohansebas]

I don't see a reason why the code needs to be compiled unless it's to generate the TypeScript files. Is there any reason why you can't use Multer in .cjs files?