List Greenhouse scheduled interviews and fetch interviewer availability for scheduling coordination

Steps

1. GET https://harvest.greenhouse.io/v1/scheduled_interviews to list all upcoming scheduled interviews; filter by job_id, application_id, or created_after/created_before query parameters to scope results.
2. Each scheduled interview object contains an interviewers array with the Greenhouse user_id, name, and scorecard_submitted status for each interviewer.
3. To check interviewer availability within Greenhouse (if using the Interview Kit feature), GET /v1/users/:user_id to retrieve the user's profile and linked calendar connection status.
4. Cross-reference the interviewers against GET /v1/users to build a complete roster with email addresses for external calendar coordination.
5. To create a scheduled interview, POST /v1/scheduled_interviews with application_id, interview_id, status, and interviewers array containing user_id entries.
6. Update a scheduled interview (e.g., reschedule) with PATCH /v1/scheduled_interviews/:id providing updated start, end, and location fields.