summary.by_evidence_authority bucketed each obligation's source_state, so a
shipped-artifact and a controlled-replay ledger returned the same summary and
the promised authority breakdown was unanswerable.
Derive the buckets from authority_references[].authority using the Evidence
authority vocabulary owned by the Evidence schema. An obligation counts once
under each distinct authority it cites, so counts can exceed total. Keep the
source-state histogram under its own name, by_source_state. The readiness
example now derives its summary from the same owner function instead of
hand-writing buckets.
BREAKING CHANGE: summary.by_evidence_authority keys are now Evidence
authorities (shipped-artifact, controlled-replay, historical-reference,
external-service, analyst-inference) instead of source states. The previous
state counts move to the new required summary.by_source_state. Ledger closure
digests change accordingly.
Fixes#5838
Co-authored-by: Claude Opus 5.5 <noreply@anthropic.com>