Interview stages are the steps of a job's interview plan — for example Application Review, Phone Screen, Onsite, and Offer. Each stage belongs to a job and is referenced by job_interviews (the slots within the stage) and by application_stages (the per-application history of which stages a candidate has occupied). Every plan starts with Application Review (sort_order: 0) and ends with Offer; the stages in between can be picked from the Greenhouse stage library or created custom per job, so names and counts vary across jobs in the same organization. Scope the list with parent=job plus ids to pull the plan for one or more jobs; inactive stages are included by default and can be filtered out with active=true.