Make WebManager.Generator faster

[Codelisk]

Read how to improve performance of code generators
https://andrewlock.net/creating-a-source-generator-part-9-avoiding-performance-pitfalls-in-incremental-generators/

try to make WebManager.Generator and WebManager.Generator.Contracts faster

you can also try to find a new way to create the contracts because currently it works with a direct reference to WebManager.Generator which is not so nice. If possible keep it so that WebManager.Generator.Contracts can be used as a seperated Generator so that its still possible have the Contracts and the implementation of the manager in 2 different projects. If not halb so schlimm.

Thats how you can debug the generator
https://github.com/JoanComasFdz/dotnet-how-to-debug-source-generator-vs2022