We should at least consider adding a trim-friendly attribute to MessagePack and add the analyzers necessary to ensure proper execution under NativeAOT.

See these resources:

• https://devblogs.microsoft.com/dotnet/creating-aot-compatible-libraries/
• https://learn.microsoft.com/en-us/dotnet/core/deploying/trimming/prepare-libraries-for-trimming
• TypeShape-CSharp

Being able to assert this will likely have spillover benefits for unity.