fix: add cjs format support

[ycjcl868]

Close #90

[jspahrsummers]

This change appears to inline every file's imports into the output version of that file (CJS and ESM).

If you can fix that up—so that cross-file imports/requires work as expected—we can consider pulling this in.

If not, note that CJS support is not a priority for us.

[ycjcl868]

fix

I’ve updated the code. Please review it again.

[jspahrsummers]

Thanks for the fixes! I checked out this out locally and took it for a spin, and it looks pretty reasonable to me.

I'm going to merge this, and let it sit on main for a bit while folks give it a try—just to make sure there are no unexpected issues—then push a new package release later.