[nggmsg] New port

[xhk]

添加nggmsg库的vcpkg.json和portfile.cmake配置文件，支持通过vcpkg安装该库

• Changes comply with the maintainer guide.
• The name of the port matches an existing name for this component on https://repology.org/ if possible, and/or is strongly associated with that component on search engines.
• Optional dependencies are resolved in exactly one way. For example, if the component is built with CMake, all find_package calls are REQUIRED, are satisfied by vcpkg.json's declared dependencies, or disabled with CMAKE_DISABLE_FIND_PACKAGE_Xxx.
• The versioning scheme in vcpkg.json matches what upstream says.
• The license declaration in vcpkg.json matches what upstream says.
• The installed as the "copyright" file matches what upstream says.
• The source code of the component installed comes from an authoritative source.
• The generated "usage text" is accurate. See adding-usage for context.
• The version database is fixed by rerunning ./vcpkg x-add-version --all and committing the result.
• Only one version is in the new port's versions file.
• Only one version is added to each modified port's versions file.

[BillyONeal]

The name of the port matches an existing name for this component on https://repology.org/ if possible, and/or is strongly associated with that component on search engines.

Would you accept xhk-nggmsg ? That would follow the GitHubOrg - GitHubRepo pattern for which we do not require demonstrating that the name is strongly associated with that upstream.

[BillyONeal]

It seems like you probably want this to be named something like nggmsg? This is the name the rest of the world expects to say when they name your library.

[BillyONeal]

Is vcpkg's generated usage text incorrect? We generally avoid including full examples, and this case isn't even really an example because the library isn't used. Moreover, portfile.cmake suggests find_package(my_sample_lib but you don't show that here.