Flip ephemeral + active sources with no recent activity to archived.
Scoped to the caller’s sandbox. Idempotent — running it twice archives zero additional sources the second time. Chunks and graph events are never touched; only the source record’s status changes, freeing quota.
Intended to be hit by an external scheduler (Cloud Scheduler, cron, or an agent loop) on a cadence appropriate to the inactivity threshold.
Bearer authentication header of the form Bearer <token>, where <token> is your auth token.