F# regression test suite

As F# is part of dotnet-sdk and many aspnetcore features now involve source generators, it would be good if a .fsproj was added in the tests section having unit test coverage for what works and showing also what currently doesn't. C# is a great language but soon it's functional feature expansion will have its limits, likely is cheaper to accomodate for F# in the long term plan, now with llms that's also much easier and would be a good investment for the lesser known but awesome C# cousin.

Other big .NET libs are written or have supported testing for F#, the dotnet "community" and Ms might think of follow the example of Xunit and Pgsql? This is not an attack in any way but is just to shine a light on something that's maybe important and matters in the long term design. |> please take this into consideration aspnet team 🎅🏿🤶🏽🧑🏻‍🎄✨💚

Start by examining the SDK's tests section and existing test-project layout, then determine where an F# .fsproj would fit. Define unit coverage for source-generator scenarios that work and those that do not, and use the resulting test suite to establish what completion means.

Written by the indexing model from the issue text.