Add types in the package

[mathieutu]

Hey, thanks for your work!

Is your feature request related to a problem? Please describe.
Your package is written is TS.
The package.json had a types entry to dist/index.d.ts but this file doesn't exist.

I would be quite handy to have them to be able to import and use the methods directly.

Describe the solution you'd like

- "declaration": false,
+ "declaration": true, 

in tsconfig.build.json

Describe alternatives you've considered
🤷
Additional context
Happy to do the PR.
Thanks!

[paleite]

Hi, good idea!
Please do the PR if you have the time, otherwise I will be able to do it myself fairly soon.

Thanks for the suggestion