* add prometheus stats for rtt/jitter/packet loss
* add track source to metrics
* better packet loss bins
* add track type to metrics
* remove source from AnalyticsStat
* regenerate telemetry service fake
* compute loss from per stream packet count
Related to livekit/protocol#273
This PR adds:
- ParticipantResumed - for when ICE restart or migration had occurred
- TrackPublishRequested - when we initiate a publication
- TrackSubscribeRequested - when we initiate a subscription
- TrackMuted - publisher muted track
- TrackUnmuted - publisher unmuted track
- TrackPublish/TrackSubcribe events will indicate when those actions have been successful, to differentiate.
In certain scenarios such as migration, we do not want a duplicate event
to be sent when the participant is reconnecting. The Prometheus metric
should still be updated though.