A source-fallback percentage stopped being a readiness signal once
bincraft learned to keep a matching-minor generic binary out of a
fallback's shadow. What survives now is the case where the generic
binary was built under a different minor: unsafe for this client anyway,
so serving source is correct, just slow. Failing on that share would
block slots that are in fact ready - amd64/noble sits at 53% for 4.5 and
4.6 while regressing nobody.
Gate on the thing that decides it instead: packages this client would
receive as source through per-minor routing while the generic slot holds
a binary built under its own minor. That is strictly worse than not
routing, and must be zero. Fallback share is still printed, as context
rather than a verdict.
Measured zero across every reindexed slot and minor.
pat-s
cfa552f54e