Show progress about requests in timeline

It's cool to show the progress about request in timeline, we can see only when the request receive some response or when it falls in timeout. I think it's importante because as we can't see the progress, sometimes seems the request doesn't called.

I'm using the Reactotron `v2.17.1`

Start by tracing how requests are represented in the timeline and where response or timeout events are recorded. Determine how progress can be exposed during an in-flight request, then verify that the timeline visibly updates before the request completes.

Written by the indexing model from the issue text.