🎉 Migrated to .NET 9.0

[winstxnhdw]

lc-hax now requires .NET 9.0 to compile. With Zlinq, we can expect some performance improvements.

If you are still on .NET 8.0, install .NET 9.0 now: https://dotnet.microsoft.com/en-us/download/dotnet/thank-you/sdk-9.0.300-windows-x64-installer