Apply and Supersede updated an intention by id alone, so a reconsideration
from the event bus and one from the executor could both apply: an
intention abandoned on goal_abandoned could be resumed by resumeParent a
moment later, leaving it active with closed_at set. Each transition now
writes only when the status is still the one the caller read, before its
event and decision, and a lost race returns ErrClosed having written
nothing. Plan SetStatus likewise changes only an open plan or a draft, so
a stale copy can never relabel a completed, failed, abandoned or
superseded plan. Regression tests cover both.
Andy Dixon
581e9009cd