An asker started before its grant was composed was refused once and stayed deaf until it started again, silently.
DeadLetterHearing tries in the background and again on an event (Again: a reconnect, an ask waited for while deaf), and
tells each change of Hearing so the module's health tool can say it. DeadLetterReads drops the flow control a pull
consumer does not use and deletes one consumer by name.
A check ask given up during a bus reload left its try running for ever: the asker had no grant to learn that
DEAD_LETTERS holds it. DeadLetterReads grants an ordered consumer on DEAD_LETTERS filtered to the seat stream's copies,
and nothing else of the stream.
The grants part composes the bus's user list with the composer the controller uses (ADR 0547 §5), copied rather than
moved: the controller is not changed and keeps its own until it loses the lease. Left out: the bus client, the broker's
address from the environment and the client's two methods; the lease's two subjects are copied in.
One table test holds the copy to four meshes' lists and the server golden, written by the controller's own
internal/broker from the same fixtures (testdata/controller-user-lists.json).
jschoubben