Tier C schedule push (plan 24 phase 3): the agent (via the SDK's observeScheduler wrap, or plain curl) POSTs a read-only projection of its own scheduler the moment it changes:

{"schedules": [{"id": ..., "nextRunAt"?: ISO, "cron"?: "5-field",
                "tz"?: IANA, "prompt"?: str, "name"?: str}, ...]}

The list is reconciled AUTHORITATIVELY through the same byo_sync provider the Tier B GET /schedules poll uses, so push and poll can never fight: sending the full current list adds, updates, and garbage-collects in one call. An empty list clears all synced wakes.

Returns {"upserted": n, "deleted": n, "desired": n}.