Replace Pluralsight.Crypto library with a cross-platform alternative

[markjamesm]

Currently Dioscuri only builds on Windows. This is because the library used to generate an X.509 certificate (Pluralsight.Crypto) is on .NET Framework and makes win32 API calls:

Package 'Pluralsight.Crypto 1.1.0' was restored using '.NETFramework,Version=v4.6.1, .NETFramework,Version=v4.6.2, .NETFramework,Version=v4.7, .NETFramework,Version=v4.7.1, .NETFramework,Version=v4.7.2, .NETFramework,Version=v4.8' instead of the project target framework 'net6.0'. This package may not be fully compatible with your project.

Need to replace this library, possibly by making use of the .NET CertificateRequest

[markjamesm]

Dioscuri now builds on Mac, but there's a bug in which a certificate validation error occurs. Need to investigate further.

[markjamesm]

When Gemini.Fetch is set to secure mode, the Client crashes on Mac when a new request is made. Looking at the code inside the SmolNetSharp library, I need to debug what might be happening with the certificate chain on Mac.

connectInsecure variable

AlwaysAccept:

https://github.com/markjamesm/Dioscuri/blob/master/SmolNetSharp/Gemini.cs#L139