Annotate congestion graph with qlog events

[MarcoPolo]

Is your feature request related to a problem? Please describe.
Would be great to see qlog events show up in the graph.

Describe the solution you'd like
graphs shows a mark that on hover expands to the qlog event.

[rmarx]

Hey @MarcoPolo,

Which events specifically would you like to see in there? Displaying all of them would become very cluttered very quickly... could you give some example use cases where you'd like more info than the graph shows now?

[MarcoPolo]

I think a generic way to say "I would like this event to show up in the graph" would be helpful. I'm debugging auto-tuning and correctly setting the flow control limits. In this context seeing when the sender stopped sending because it was blocked would be helpful. Maybe a vertical line at the time an event was logged would be good enough for this use case (along with full event info on hover).