[VBLOCKS-1379] Incoming call screen hooks and actions

[mhuynh5757]

Submission Checklist

• [ ] The CHANGELOG.md reflects any feature, bug fixes, or known issues made in the source code
• [x] New unit tests and integration tests have beed added
• [x] Code coverage is more or equal to the previous coverage
• [x] A visual inspection of the Files changed tab was made prior to submitting the pull request ensuring the style guide was followed
• [x] CI pipeline is green
• [x] Included screenshot if necessary

Description

Refactor and modify application state to allow for Incoming Calls.

Breakdown

• Move user slice out of voice slice.
• Adjust async slice state to model an idle state properly. This is helpful when extending the type since the idle state is now a distinct type and not an inference on null.
• Create the active call slice and bind it to incoming and outgoing call actions.

Validation

• Tested existing outgoing call functionality manually.

Additional Notes

Note that without the incoming call components, the incoming call hooks and actions are only testable via unit tests. Manual testing of the incoming call feature end-to-end will come later.

Contributing to Twilio

All third-party contributors acknowledge that any contributions they provide will be made under the same open-source license that the open-source project is provided under.

• [x] I acknowledge that all my contributions will be made under the project's license.

[mhuynh5757]

Live review notes:

• Address ongoing feedback from @kpchoy and @charliesantos
• ~Fix CallInvite types~
• Test again to make sure existing features work, make base branch main if all is good
• Changelog and readme information when incoming call work is all done, after component work
• @charliesantos to do another pass

Edit: decided not to do the CallInvite changes

[mhuynh5757]

Update: tested existing functionality to ensure no regressions.

[charliesantos]

Update: tested existing functionality to ensure no regressions.

@mhuynh5757 as discussed, since there are no breaking changes and it's a large PR, please submit this to the main branch to avoid conflicts.

[mhuynh5757]

Rebased onto main.

[charliesantos]

Reviewed the checklist. +1!