No disk-preserving recovery for a storage-wedged sprite: restore unreachable, no stop/restart API, documented DELETE exec returns 404 #231

Companion to the disk-I/O-wedge report in #230. When a sprite's storage wedges while the VM stays running, every disk-preserving remedy turns out to be unreachable, and the owner's only exit is sprite destroy — losing checkpoints, credentials, caches, everything. Verified on supervisor 0.0.1-rc47 (2026-08-24) and again on rc48 (2026-09-01), org junchao-yan:

1. Checkpoint restore routes through the wedged overlay manager. GET /v1/sprites/{name}/checkpoints hangs forever, and restore needs the same manager — so the one mechanism designed to recover a broken overlay is unavailable precisely when the overlay is broken.

2. There is no stop / suspend / restart verb in the CLI or the public API (checked rc47 and rc48; docs confirm). A plain machine stop/start preserving the volume would very likely clear the wedge (it is VM-side mount state, not necessarily volume data), but there is no way to ask for one.

3. DELETE /v1/sprites/{name}/exec/{id} returns 404 despite being documented (verified on rc47), so the zombie exec sessions that pile up from client retries cannot be cleared.

4. The container cannot be stopped either: POST .../services/container/stop → "service not found" (the user container is a hooks-managed service, not in the services API).

5. Idle-suspend never fires as an escape hatch. After quieting all clients, phantom http: activity sources persisted for 25+ minutes — server-side request handlers stuck on wedged reads (one hung checkpoints GET holds an activity source forever) plus pooled keep-alive connections — so the sprite never reaches the quiet window that would let it suspend and cold-boot.

6. Killing the container's init hold-open from inside (08-24, when exec still worked) SIGKILLed the container tree and destroyed its mount namespace — and the supervisor never logged a container exit and never recycled the VM; its teardown appeared stuck unmounting the wedged overlay.

Ask

• A supervisor- or platform-side hard recycle (stop + start with the volume intact), exposed via API/CLI, that does not depend on the overlay manager being healthy.
• Request handlers that block on storage should time out and not count as idle-blocking activity, so a wedged sprite can at least drain to suspend.
• Fix or un-document DELETE /v1/sprites/{name}/exec/{id}.