Today's progress: I got things to build on macOS. When you create a C# Godot Project, it will by default fetch the Godot assemblies from the default remote repository. For users of our custom engine build, they'll have to add a local repository to their nuget.config file. I'm also only targeting desktop OSs for the first MVP. There is simply not enough documentation regarding mobile or web with C#. The same is true for GDExtensions btw.
Once this is done, we'll publish C# builds of our Godot engine fork as well. Then there should only be one manual step for users to get their C# projects working with Spine support, namely, adding the NuGet source to point to a local copy of "our" Godot .NET assemblies.
