ADR 0582 clause 3 composes the bus's user list without the controller's write on the lease key and update of
the lease's bucket. Records.LeaseCut, set by the grants part from the write's second step, drops the
controller's $KV grant on the lease, denies it the bucket's update, purge, delete and message delete (its
$JS.API.> reaches them), and lets the grants part write the key holder alone. The bus module's tools account
may read and update the lease's bucket, for the expiry tool the write and the hand-back call. Without the cut
the lists equal the controller's golden.
Tests: rows added to TestTheCopiedComposerComposesAsTheControllers' tables (the cut on and off; the tools
account's lease grants); no new test function.
(issue 774, 774/S2)
Claude-Session: https://claude.ai/code/session_01NcbgfJ9Gum47zkFKWRaovL