The Windows completion child (dependency sync, product builds) was started running and
bound afterwards, so a fast grandchild could escape the update's kill-on-close job, and
a refused bind was only a log line. It is now created suspended, bound, then resumed.
Post-commit a refused bind still runs it (ruling: refusing would fail a committed
update), but never silently: the refusal is printed and recorded as a failed
update_custody step in this run's receipt and in the receipt the child resumes (its
request is rewritten before it runs), so the terminal receipt carries it.
Windows live cell: the real AssignProcessToJobObject refuses an event handle; the
child must not have run at bind time and the step must reach the child's receipt.
2e3cecd099