Adds Call Status events for granular call insights

[cybex-dev]

Contributing to Twilio

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Pull Request Details

Description

Adds granular Call status events to provide more insight into the current call state.

• Introduces Call.CallStatus enum for detailed call status reporting.
• Emits 'status' events during various stages of the call lifecycle, such as connecting, connected, ringing, etc.

Use-case:

• Provides a status hook for call monitoring in 3rd party plugins, such as Flutter's twilio_voice package monitoring calls for Flutter Web, see https://github.com/cybex-dev/twilio_voice/blob/master/lib/_internal/twilio_voice_web.dart#L862

Burndown

Before review

• Updated CHANGELOG.md if necessary
• Added unit tests if necessary
• Updated affected documentation
• Verified locally with npm test
• Manually sanity tested running locally
• Ready for review

Before merge

• Got one or more +1s
• Squashed erroneous commits if necessary
• Re-tested if necessary

[kpchoy]

Hi @cybex-dev thank you for your contribution. I see a majority of these events are already emitted by the Call.Events. Please see https://www.twilio.com/docs/voice/sdks/javascript/twiliocall#events .

[kpchoy]

Will close this PR due to inactivity. Please open another PR or issue if your issue persists, thanks.