BuildCheck suggestion: Evaluation time Item points to the output of a project

[JanKrivanek]

Context

Inspired by #6198 and https://github.com/benvillalobos/msbuildism/tree/main/including-generated-files

When adding an evaluation time item update/include that is attempting to point to build execution time produced files - such item can either plainly not work as intended or worse behave differently based on build order leading to possible undeterministic behavior of the build

Goal

Implement a Check with the following rule: items updates/include happening during evaluation time are not allowed to reference outputs or intermediate outputs of projects that are part of the build.

[rainersigwald]

I'm not sure this is a good idea; it's perfectly ok in several cases to have an item that doesn't exist on disk yet, as long as it does before it's used. In general, you want to discover reference items from other projects by asking them (the normal p2p protocol) but for some more advanced scenarios a "dangling reference" is ok.

The only time I think it would be required is for a task defined in another project (since the UsingTasks are processed before targets) but I bet users have done this a bunch.