servedOnThisMachine stopped at the first module whose `serves` mentioned the
provision, even when that entry was empty and there was therefore no fact to give
a consumer. here() had always kept looking in that case, and a set where one
module names a provision without describing it and another describes it is exactly
where the difference shows. Restore the search.
Claude-Session: https://claude.ai/code/session_01LrgweAeERJYBg88c5cKDzF