[Feature] - Switch to .NET 10 SDK

[smaillet]

Is your feature request related to a problem? Please describe.
The global.json currently restricts the repo builds to the .NET9 SDK. However, the IDE is ignoring that and using whatever compiler is built-in causing discrepancies between an IDE build and the command line. Automated builds use ONLY the command line. The IDE is WRONG here. Supposedly as of .NET 10 SDK that behavior is different and now uses the correct tooling. Additionally the .NET 10 SDK includes C# 14 so everything in the project can be updated to target .NET10 and use that.

Describe the solution you'd like
.NET 10 SDK is used and .NET 10 is the target runtime.

Describe alternatives you've considered
Leave it on .NET 8, but that is not the latest LTS so runs out of support.

Additional context
Requiring a new .NET target and dropping an old one is a breaking change so is best left to 21.*