The builder's build.ended is said for a failed build as well (outcome, error whole);
the assigner's rule-1 hold reads "the build of M at F failed: <error>" from it and
"is being built" while none is heard. The assigner's reads of the builder's builds
bucket stay (see the report: a restarted assigner holds no ends heard).
Builds: design 47 G §575, §568, A-162 (survey AS23)
Claude-Session: https://claude.ai/code/session_01NcbgfGKaxw984XyAPfLm4h