feat(pre-push-safety-net): record admission vetoes and meet M1a on NodeGoat

Add group 9 to the approved task plan as the bounded owner amendment release
milestone M1a requires, implement the task-local recorded-veto evaluation flag,
and run the three pinned NodeGoat revisions under it.

The flag re-runs the production comparison and admission over a lifted copy of
the same evidence and records each veto instead of applying it. Recognized
completeness vetoes are lifted and logged; failures never are, because silence
from a failure is not a quiet fixed twin. It is off by default, accepted only on
explicit base/head replay, refused in Git stdin mode, labels every payload it
produces, and admits no defect even when a lifted candidate otherwise would.

M1a outcome, inside its one-week box and with expectations frozen on disk first:
the three entailed <lambda>2 witnesses are present at contributions.js 32-34; the
fixed twin was genuinely analyzed and quiet, answering its target question with
zero rows and no deadline reason while the same findings appear as base-only; the
unchanged revision was analyzed and recorded unchanged. The kill criterion did
not trigger.

Five vetoes fired and were recorded. M1a also corrected the diagnosis: with all
five lifted the detection still stops at operation_correspondence_unresolved,
because a newly introduced operation sits on a changed line and has no base
anchor. The unchanged revision resolves its base location on the same lines and
classifies as unchanged, which isolates correspondence as the mechanism. That
fifth veto was not in the earlier four-veto diagnosis and is now M1b's central
repair.

Diagnosis only. No defect admitted, no capability enabled, no gate changed, no
latency claim; the 900-second development budget cannot measure the hook gate.
Rollout and task 8.3 remain NO-GO.

Co-Authored-By: Claude Opus 5 (1M context) <[email protected]>
Claude-Session: https://claude.ai/code/session_01EmM1j46qgKMh3zqD1QMwEo

.kiro/specs/pre-push-safety-net/release-milestones.md

@@ -8,8 +8,8 @@ It does not approve an unreviewed implementation design or enable any capability
 
 ## Current position
 
-**Next milestone: M1a. None of M1–M5 is verified yet.** The 26/27 completed executable
-tasks measure implementation progress, not release readiness. Task 8.3 remains blocked.
+**Next milestone: M1b. M1a is met; none of M1–M5 is verified yet.** The 28/29 completed
+executable tasks measure implementation progress, not release readiness. Task 8.3 remains blocked.
 The published `v1.2.0-alpha.1` is an experimental implementation release, not a qualified
 advisory rollout. See [current status](status.md) for measured evidence and limitations.
 
@@ -37,8 +37,14 @@ result is a full production pass, not one detection.
 
 ### M1a — Show the detection with every veto recorded
 
-Status: **NEXT — not verified**. Time box: one week of maintainer effort from the first
-M1a run. Missing the box is a finding, not a reason to extend silently.
+Status: **MET 2026-09-16**, inside its one-week box. Evidence:
+[M1a record](m1a-recorded-vetoes.md) and
+[measurement](../../../benchmarks/measurements/2026-09-16-nodegoat-m1a-recorded-vetoes.json).
+Raw witnesses present at contributions.js lines 32–34; fixed twin analyzed and quiet with
+zero rows and no deadline reason; unchanged revision analyzed and recorded `unchanged`. The
+kill criterion did not trigger. Five vetoes fired and were recorded, and M1a corrected the
+diagnosis: with all five lifted the detection stops at `operation_correspondence_unresolved`,
+a fifth veto that was not previously named. No defect was admitted and no capability enabled.
 
 - Use the pinned NodeGoat contribution injection case, its fixed twin and an unchanged
   vulnerable revision as development data. Record exact base/head revisions, expected
@@ -63,7 +69,11 @@ diagnosed and recorded.
 
 ### M1b — Repair only the vetoes M1a showed to matter
 
-Status: **PENDING M1a**.
+Status: **NEXT — not verified**. M1a supplied the veto list: per-family change context,
+question-owned vendor relevance, operation correspondence for an operation on a changed line,
+file-wide correspondence ambiguity scope, and query-to-operation provenance. The owner
+diagnosis expected the first and the last two; operation correspondence is the addition M1a
+measured and is the blocker that survives every other repair.
 
 - From the M1a veto list, repair only the context/family/identity contracts this case
   actually needs. The owner diagnosis expects query-to-operation provenance and question-
@@ -192,9 +202,10 @@ remaining blocker and next concrete action. Report implementation task counts se
 Change a milestone to verified only with linked evidence; do not infer progress from
 elapsed effort or a completed experimental release tag.
 
-Immediate next action (M1a): add the task-local recorded-veto experimental flag, run the
-NodeGoat vulnerable, fixed and unchanged revisions under it, and produce the per-finding
-veto list alongside the `<lambda>2` witness. Then trace that witness into the declared
-contribution handler and turn the vetoes that actually fired into the smallest owner fix
-(M1b). Use [remediation research](../contributor-scan/release-remediation-research.md) as
-the starting record; do not begin another broad timing campaign before the M1 outcome exists.
+Immediate next action (M1b): repair the five vetoes M1a recorded, smallest first, starting
+with operation correspondence for an operation on a changed line, since that one survives
+every other repair. Then rerun the same three revisions without the flag through the
+production evidence and comparison rules. Use
+[M1a evidence](m1a-recorded-vetoes.md) and
+[remediation research](../contributor-scan/release-remediation-research.md) as the starting
+record; do not begin another broad timing campaign before the M1 outcome exists.