The operator asked to remove the controller by finishing its hand-over; no tool said who holds
the lease, which manifests still read, invoke or consume mesh-controller, or whether the lease
write's check (ADR 0571 §13) would pass. grants_lease_check answers all three from bus state on
the grants part, which already reads the lease, every manifest at the indexer's trunk and the
bus's streams: the holder and what follows from it, every dependency with the record on the
named keep list that keeps it, the controller's streams and buckets someone consumes, and the
check run dry at the write (the three kept to it alone) and before its delivery, with reasons.
Quick fix: the judgement and the keep list in the grants part, as here.
Thorough fix: the keep list and the dependency derivation in mesh-sdk, shared by this tool and
the §13 manifest tests in mesh-catalog, mesh-delivery and mesh-tools. Chosen quick: the tests do
not exist yet and an sdk move needs a group; the move is named for the lead.