workflow-fix: verify_plan.py resume-provenance check (persist+resume-skip plans must name input-fingerprint validation)

Overview / Motivation

Auto-filed from a prose workflow-gap note surfaced by the codex-critic (alternatives lens) during #952's kfold-decision-cells plan review (2026-07-05): "This is a recurring workflow-surface verifier check: fold/resume consumers should mechanically validate input fingerprints, not just output existence." The #952 v9→v10 revision added the check as a REGISTERED plan gate (gate-5 provenance manifests) for that one experiment; the generalizable half is a verify_plan.py surface check.

Goal

Add a verify_plan.py check (WARN experiment/analysis): a plan that names a per-unit persist + resume-skip pattern (resume, checkpoint-skip, per-fold/per-cell persist) must ALSO name an input-fingerprint / provenance-manifest validation for the resumed outputs (split hashes, code SHA, env knobs — any recognizable fingerprint token near the resume mention), not just output existence.

Workflow gap

• Bug observed: #952 plan v9 prescribed per-fold persist + resume-skip with no provenance contract; a crash + code-fix round would let stale-fold outputs (or a stale calibration gate PASS) silently vouch for post-fix verdict folds. Caught only by the critic ensemble (reconciler-binding REVISE).
• Why it is a workflow gap: resume-skip-without-fingerprint is a recurring plan shape (the intra-phase persist law mandates per-unit persist for >1h loops, so every long battery plan writes one); the verifier has checks for battery arithmetic (c12) but nothing for resume-provenance.
• Confidence (emitter): medium (Codex prose note + a reconciler-verified live instance).

Scope / surfaces

• Primary target: scripts/verify_plan.py (+ tests/test_verify_plan.py)
• Window-scoped like c12 (±15 lines of a resume/persist mention); canonical N/A phrase for plans with no resume pattern.

Constraints / invariants

• WARN not FAIL in v1 (surface check; semantic adequacy stays with the critics); workflow_lint + existing verify_plan tests stay green.

Provenance

• workflow_fix_target: scripts/verify_plan.py
• origin: codex-critic alternatives-lens prose note on #952 plan v9 (2026-07-05); adopted as #952 plan v10 gate-5 for the instance