refactor: replace kolorist with kleur/colors

refactor: replace kolorist with kleur/colors

The size of `outfile.cjs` before the change:
143037 bytes

Ater the change:
141514 bytes

Saved 1523 bytes.

I didn't choose `picocolors` despite it being more popular because
it doesn't support tree-shaking and actually increases the bundle size
a bit.

I didn't choose `yoctocolors` because the resulting bundle is also a bit
larger than the one produced by `kleur/colors`.

Addressed the issue raised in #253