Embed api call and update attribute generation

[waynebrantley]

@Dreamescaper Are you wllling to add the Embed api call into your attribute generation? Its a one line add..

https://andrewlock.net/exploring-dotnet-10-preview-features-4-solving-the-source-generator-marker-attribute-problem-in-dotnet-10/

This would make this source generator require dotnet 9 or later...This would eliminate the warnings and such that are currently generated in my situation.

[Dreamescaper]

I'll have to investigate backward compatibility question first, but generally yes