The store's nightly collector deleted the bare blobs of node-tools', mesh-host's and the forge bridge's done keys, which
the controller had never taken in, and the builder kept them done: their next delivery would refuse. The builder now asks
the controller's held before it leaves a done trunk key done (once per key per process, at its start and on each module
value), claims a key whose blob is gone building as a new revision and says so in its log and the key's step, and hears
artifacts-gone, said when a take-in found a gone blob. No timer: a start, a value or an event.