publish only necessary files, make ts friendly

[Swolebrain]

Description of changes

Preparing to publish this to npm. We don't need to export every file, and we should make it ts-friendly.

Issue #, if available

n/a

Checklist for requesting a review

The change in this PR is (choose one, and delete the other options):

• A change "invisible" to users (e.g., documentation, changes to tests, refactoring, etc.)

I confirm that this PR (choose one, and delete the other options):

• Does not update the CHANGELOG because my change does not significantly impact released code.

Disclaimer

By submitting this pull request, I confirm that you can use, modify, copy, and redistribute this contribution, under the terms of your choice.