[BUG] Package was made ESM-only in a patch release

[jakebailey]

Version 1.3.8 switched the package from CJS to ESM. This is a breaking change, and should have been made in a major release bump.

This was caught on DefinitelyTyped, which contains community-supported types for this package. https://github.com/DefinitelyTyped/DefinitelyTyped/actions/runs/11013392257/job/30581700193#step:12:2874

Would you consider reverting 1.3.8's changes in a v1.3.9, and republishing as a v2 to unbreak this?

[jakebailey]

Additionally, modules were moved around, which is a breaking change too :(