add more instrumentation

[AdiSai]

This PR adds/exposes the following events for instrumentation:

'camera-error' (daily.co),
'network-quality-change'  (daily.co),
'network-connection'  (daily.co),
'call-start-progress' (custom to track progress of call start),
'call-start-success'  (custom to indicate a successful call initiation),
'call-start-failed'  (custom to indicate a failed call initiation)