Add support for build.zig.zon and use of zigs new fetch command

[Tired-Fox]

Zig v0.12.0 brings in the support for build.zig.zon. This means that the generated code could also generate this file allowing users to use the zig fetch --save https://github.com/marlersoft/zigwin32/archive/main.tar.gz command to add the library as a dependency. Could be a static file that has it's version bumped with each release. Then the file is copied on generation similar to the build.zig file.