Mark TSServer reponses affected by `updateGraph` calls

[DanielRosenwasser]

TSServer logs currently get very noisy with updateGraph calls, but it's not clear what is actually the cause of the work being done there. From discussion with @amcasey, it sounds like a reasonable solution is to have TSServer responses should indicate that they're forcing updateGraph calls.

[amcasey]

The goal here is not to determine what triggers graph updates, but which operations are affected by updateGraph computations (i.e. delays), how often, and to what extent.