Backup lines are derived from each module's data section instead of written by hand; the holder
measures declared items, reads the array under them, and deletes a retired item only after a last
restore point; the Go providers say each held consumer's size so an empty replacement is seen.
The node-build-agent seat now promises these verbs, and a holder that does not
name them cannot hold it. The binary serving them is mesh-controller's
cmd/mesh-builder; merge only once a controller carrying the seat's new verbs runs,
since an older one refuses a claim naming verbs its row lacks.
"mesh_novox_build_agent" is 22 characters; the mesh refused to send the control node its declaration
for it. "agent" keeps the identifier within what an S3 access key allows on every machine.
The builder's manifest with one change that matters: it claims node-build-agent, a node seat, so it
is assignable to every machine with a container runtime, and every holder pulls one build at a time
from the role's one work queue. A tier of many images is then built by as many machines as hold the
seat and are online. The builder module stays until this is assigned where it was; then it goes.
jochen