GeoJSON I/O uses the platform locale encoding instead of UTF-8

[saidy-moregeo]

open() is called without encoding in four places, so GeoJSON is read and written in the
platform locale — UTF-8 on Linux/macOS, cp1252 on Windows. RFC 7946 §3 requires UTF-8.

[m-mohr]

vecorel-cli has been released with your changes, so you can update here.