* In the `config.json` file, the ISO code representing Korean should be
`ko`, not `kr`.
* Remove the `client/public/locales/kr` subdirectory.
* Add the `client/public/locales/ko` subdirectory, which itself is the
OmegaT project for the Korean translation of `lean4game`.
OmegaT[0] is a translation memory application intended for professional
translators. I use it to translate English documentation into Korean.
[0] https://omegat.org/