[♻Housekeeping] Improve our NuGet package quality

[pictos]

Today our NuGet package isn't great and after watching this amazing talk from Claire I saw that we can make our package even better!
Helping users to see our code from VS, and debug our code which will help us fix bugs (since the users can provide more complete information), we can prevent breaking changes, etc...

I'll open one PR per item, to make it easy to review it and see if our CI will be happy.

[ ] Add Source-Link
[ ] Turn-on package validation

[brminnick]

https://github.com/dotnet/sourcelink

[pictos]

@brminnick should we remove the package added by the #93?

[brminnick]

No worries! #93 was never merged ✅

[pictos]

Oh, I thought this was the MCT repo. We merged the package there

[brminnick]

No worries there too! Vlad removed it in the .NET 8 PR