Research — merge-squash-provenance-and-rollback-coherence-01KXRRB7
Pre-spec research squad findings (four lenses) live in research/:
lens-a-squash-artifact-reconciliation-2709.md— #2709 clobber site (lanes/merge.py-X theirs) + reconciliation seam.lens-b-rollback-resume-coherence-2711.md— #2711 structural root cause (non-transactional rollback/resume).lens-c-shared-root-cause-boundary.md— shared-root verdict + scope boundary.lens-d-red-first-repro-design.md— red-first ATDD repro design.
Post-spec, post-plan, seam-fit, and post-tasks adversarial-squad findings are folded into spec.md and plan.md (see their "Squad Findings" sections).
Root cause (both): the merge core wrote to the committed target/coord branch without reconciling against the durable event-log authority. Two distinct fix surfaces, no shared call path — #2709 (happy-path -X theirs content loss) and #2711 (failure-path non-transactional rollback/resume). Fixes: per-artifact-class squash reconciliation (#2709) and Option A coord-done-revert + durable-log resume (#2711).