add new logic for past and future appointments

[drewconnelly]

Summary

• This work is behind a feature toggle (flipper): NO
• This change adds 3 new fields to the VAOS appointment API response: past, pending, and future. These boolean fields consolidate logic that is currently being performed by the FE at:
  • https://github.com/department-of-veterans-affairs/vets-website/blob/main/src/applications/vaos/services/appointment/transformers.js#L64
  • https://github.com/department-of-veterans-affairs/vets-website/blob/main/src/applications/vaos/services/appointment/transformers.js#L76
  • https://github.com/department-of-veterans-affairs/vets-website/blob/main/src/applications/vaos/services/appointment/transformers.js#L116
    The intent will be for the front-end to use these new API fields, removing the need for the FE transformer logic.
• Unified Appointment Experience team

Related issue(s)

• Move any existing logic for Past appointment logic to vets-api va.gov-team#99469

Testing done

• New code is covered by unit tests
• Ensure that all appointments returned from the VAOS /appointment and /appointments endpoints contain past, pending, and future boolean values in the base appointment response.

What areas of the site does it impact?

This change impacts the VAOS appointment READ operations.

Acceptance criteria

• I fixed|updated|added unit tests and integration tests for each feature (if applicable).
• No error nor warning in the console.
• Events are being sent to the appropriate logging solution
• Documentation has been updated (link to documentation)
• No sensitive information (i.e. PII/credentials/internal URLs/etc.) is captured in logging, hardcoded, or specs
• Feature/bug has a monitor built into Datadog (if applicable)
• If app impacted requires authentication, did you login to a local build and verify all authenticated routes work as expected
• I added a screenshot of the developed feature

[devin-mccurdy]

LGTM