feat(Streams)!: Stats/error logging polish

[bartelink]

Add

• Stats: DumpState to include custom output alongside internal ones
• Generalize stats gathering to LatencyStatsSet
• Add index and eventType properties to Unhandled exception logging
• Emits stuck/failing stream names in head batch State output after failTheshold (defaults to StateInterval)
• Reordered output so it gets emitted after the normal Stats on shutdown
• Ingester emits state on shutdown

Change

• Sinks.StartBatched results now require a latency per result (as a TimeSpan)
• Major cleanup of internal timing/progress management