An undo of an event-minting transaction tombstoned the events graph-side
(materialize_graph_tombstones → materialize_graph_delete re-anchors/cascades a
structure whose anchor died) but never ran the ledger-side
reanchor_for_tombstone — so a structure orphaned by the undo left the graph
while staying Live in objects, with no RepairRecord. Ch6's same-step
RepairRecord MUST was unmet for undo-driven tombstones (slurs/spanners/repeats).
Fix: tombstone_undo_targets now captures each event target's voice (before the
graph half clears voice_occupancy) and runs reanchor_for_tombstone per event
target after the graph half. The orphaned structure now cascades or re-anchors
in objects with a same-step RepairRecord, agreeing with the already-updated
graph — both use the same min-survivor rule, so they converge on existence and
target. reanchor_for_tombstone gains a liveness guard (skip a non-Live
structure) so the undo's own tombstoned mints — whose stale structures-index
entries linger — aren't re-processed into duplicate repairs; the direct-delete
path already drops tombstoned structures from the index, so the guard is a
no-op there.
canonical_bytes embeds both objects and the effect log, so this corrects the
reduced state (an inconsistency never previously exercised — no existing test
broke). Regression: undo_orphaning_a_pre_existing_slur_cascades_it_in_the_
ledger_p13_d1 (cascade + recorded repair + order-independent convergence).
939 tests, convergence/equivocation/conformance green. PASS13: P13-D1 resolved.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>