This is a subset of yyson from the 0.10.0 release (July 2024)

https://github.com/ibireme/yyjson/

License: MIT

We use internally - the build system parts, tests, etc were removed since they are not used.

Added header (conduit_yyjson_interface.h) as an interface.

Added a namespace (conduit_yyson) to avoid potential symbol collisions with others embedding yyjson.

