Consider logging item adds/removes during evaluation

This issue https://github.com/KirillOsenkov/MSBuildStructuredLog/issues/113 brings up a point: items added and removed during evaluation are not logged, so the log doesn't have any trace of it.

We should consider logging item removes (not sure if logging item adds is valuable because items added and not removed are logged per project).

I'm on the fence but I think triage should discuss and consider.

Start with the linked MSBuildStructuredLog issue 113 and review how evaluation currently handles item additions and removals. Define whether removals, additions, or both should be logged and what completion criteria triage accepts; no source file or test is identified in the issue.

Written by the indexing model from the issue text.