Typed rather than left as a string so the split between the two parent writes is enforced instead
of remembered: settling is a once-only guarded transition with a completion timestamp, and it goes
through TaskClaimStore.TrySettleParent. Handing a terminal status to the progress method
is now a compile error rather than a graph that settles without a CompletedAt.
The only status a progress write may set.
Typed rather than left as a string so the split between the two parent writes is enforced instead of remembered: settling is a once-only guarded transition with a completion timestamp, and it goes through TaskClaimStore.TrySettleParent. Handing a terminal status to the progress method is now a compile error rather than a graph that settles without a
CompletedAt.