structure checkpoint

structure checkpoint "<note>" [--repo <path>] [--kind <kind>]
                                           one line into the record: it lands as a
                                           typed checkpoint under memory/checkpoints/,
                                           the same type and home as every other
                                           checkpoint here, and prints the path it
                                           wrote. memory/ is an open rung, so it
                                           commits directly — the rung is read from
                                           structure.yml, and a company that gates it
                                           gets a refusal pointing at structure propose

structure checkpoint "<note>" [--repo <path>] [--kind <kind>]