After the build ended the module pushes the packed bundle with mesh-sdk's PushBlob under
<module>/<artifact> by its digest, a candidate's as a trunk build's, and the step answers
artifact-store://<module>/<artifact>/blobs/<digest> instead of the archive's path. A push
that fails fails the step not stored: <artifact>: <the store's words>; the packed bytes are
never written to the node. The manifest requires artifact-store and places its address.