Manage endpoint lifecycle

An endpoint has a life — created, suspended, resumed, retired. Suspending is how you stop an endpoint accepting work; in the public sandbox, the guard around it is instructive.

1. 01 · Read the endpoint

   Its life-strip and posture come back on a read; the playground's object world draws them as you go.

   GET /v1/programmable-endpoints/{endpointRef}
     → result.kind ∈ found · not_found

   Note the read answers 200 with an in-band found or not_found — a stranger ref is not a 404.

2. 02 · Suspend with the returned guard

   Send the opaque lifecycleGuard from the read with the lifecycle command. A successful response returns a refreshed guard for the next change.

3. 03 · Re-read when stale

   If another change wins first, the command is rejected in-band as stale_lifecycle_guard. Re-read the endpoint, decide again from the current posture, and retry with a new idempotency key.