Reporting loaded modules/current manifest

It might be very helpful to include in the upload a Manifest showing all the artifacts/packages reachable by the code that ran. While detecting `activate()` invocations in arbitrary julia code that might crash may not be easy, we can probably rely on most users that are using `--bug-report=rr` to also provide a `--project` if they're submitting something nicely-formed, so we can just snarf that at `InteractiveUtils.report_bug()` time, before we pass it off to the child Julia process.

Start at InteractiveUtils.report_bug() and trace how the upload is handed off to the child Julia process. Determine how the supplied --project can be read at that point and define the manifest of reachable artifacts or packages that should appear in the upload; done means a bug report includes that manifest.

Written by the indexing model from the issue text.