This is 7za utility for compression/decompression of common archive formats.
Primarily used for building Unity itself.

Builds for Win64, Mac64, Linux64 come from a Katana project "SevenZip",
and are based on:

- https://github.com/Unity-Technologies/7-Zip-zstd (Windows)
- https://github.com/Unity-Technologies/p7zip-zstd (Mac & Linux)

Which means it's command line 7-Zip, plus support for Zstandard compression.
