The mesh names what may go from its own build records — a digest it did not
record making is never named, which is what keeps the sweep away from the
images genesis pushed. An artifact stays because a definition the mesh holds
names it, or because it belongs to one of the five most recent successful
builds of its module.
internal/artifacts asks the store to let go of one; internal/inventory
decides and remembers (migration 0055); the sweep runs after a build the mesh
recorded, which is when both the bytes and the keep set moved. Never fatal to
a build.
And the manifest side of while-stopped, refused from the definition alone:
no schedule, run-once, a container the module does not declare, itself.