Spec: a skipped one-off fires after the next start; the late note's placement and no-exit-code failure wording are pinned down; IsDeliverable is part of the watcher invariant and must not create a session; saves snapshot inside a serialising gate.
Spec: a skipped one-off fires after the next start; the late note's placement and no-exit-code failure wording are pinned down; IsDeliverable is part of the watcher invariant and must not create a session; saves snapshot inside a serialising gate.