- Add csharp job: builds with Mono, tests sync version
- Add dotnet job: builds both sync and async with .NET 10
- Update clients/dotnet/Makefile to support sync and async builds
- Update clients/csharp/Makefile to remove reference to deleted dotnet folder
- Add both to summary job dependencies
- Add dotnet/ directory with modern .NET 10 implementation
- Use HttpClient, async/await, and System.Text.Json
- Update Makefile to build both Mono and .NET versions
- Add comprehensive README documenting differences
- Both versions now supported in unsandbox-ubuntu container