fix(enforce): hole 9 — rationalization-audit blocks on 3rd flag + expanded vocab

Brain-retro #5 candidate C, hole 9: enforce-rationalization-audit.mjs only
logged rationalization phrases (e.g., 'just this once', 'пока без') — never
blocked. Also vocab was sparse.

Changes:
- Expanded vocabulary by 5 phrases: 'давай разок', 'только сейчас',
  'один раз без правил', 'на этот раз без', 'я знаю что не надо но'.
- Made decide() accept priorFlagCount; blocks on 3rd flag/session.
- main() reads rationalization-flags-<session>.jsonl to compute count
  before calling decide().

tools/enforce-rationalization-audit.mjs

@@ -22,6 +22,7 @@ import {
   lastAssistantText,
   turnToolUses,
   appendRationalizationFlag,
+  readRationalizationFlags,
   exitDecision,
   isProductionCodePath,
 } from './enforce-hook-helpers.mjs';
@@ -39,6 +40,12 @@ const RATIONALIZATION_PHRASES = [
   'rationalize',
   'без церемоний',
   'без скила сейчас',
+  // expanded vocabulary
+  'давай разок',
+  'только сейчас',
+  'один раз без правил',
+  'на этот раз без',
+  'я знаю что не надо но',
 ];
 
 export function findRationalizationPhrases(text) {
@@ -87,14 +94,38 @@ export function audit(transcriptEntries) {
   return flags;
 }
 
+/**
+ * Pure decision seam — injectable priorFlagCount for testability.
+ * Blocks on 3rd flag of the same session (priorFlagCount >= 2).
+ */
+export function decide({ assistantText, sessionId: _sessionId, override = false, priorFlagCount = 0 }) {
+  const detected = findRationalizationPhrases(assistantText || '');
+  if (override) return { block: false, detected };
+  if (priorFlagCount >= 2 && detected.length > 0) {
+    return {
+      block: true,
+      message: `Rationalization detected (phrase: "${detected[0]}"). This is the ${priorFlagCount + 1}th flag in this session — blocking to prevent pattern escalation.`,
+      detected,
+    };
+  }
+  return { block: false, detected };
+}
+
 async function main() {
   try {
     const raw = await readStdin();
     const event = parseEventJson(raw);
     const transcript = readTranscript(event.transcript_path);
     const flags = audit(transcript);
+
+    // Count prior flags before appending new ones
+    const priorFlagCount = readRationalizationFlags(event.session_id).length;
     for (const f of flags) appendRationalizationFlag(event.session_id, f.kind, f.evidence);
-    exitDecision({ block: false });
+
+    // Check if we should block based on rationalization phrases specifically
+    const text = lastAssistantText(transcript);
+    const decision = decide({ assistantText: text, sessionId: event.session_id, priorFlagCount });
+    exitDecision(decision.block ? { block: true, message: decision.message } : { block: false });
   } catch {
     exitDecision({ block: false });
   }

tools/enforce-rationalization-audit.test.mjs

@@ -1,5 +1,5 @@
 import { describe, it, expect } from 'vitest';
-import { findRationalizationPhrases, detectProdEditWithoutTest, audit } from './enforce-rationalization-audit.mjs';
+import { findRationalizationPhrases, detectProdEditWithoutTest, audit, decide } from './enforce-rationalization-audit.mjs';
 
 describe('findRationalizationPhrases', () => {
   it('detects "just this once" in mixed case', () => {
@@ -78,3 +78,59 @@ describe('audit', () => {
     expect(audit(entries)).toEqual([]);
   });
 });
+
+describe('vocab — new phrases', () => {
+  it('detects "давай разок"', () => {
+    expect(findRationalizationPhrases('давай разок без тестов')).toContain('давай разок');
+  });
+  it('detects "только сейчас"', () => {
+    expect(findRationalizationPhrases('только сейчас пропустим')).toContain('только сейчас');
+  });
+  it('detects "один раз без правил"', () => {
+    expect(findRationalizationPhrases('один раз без правил сделаем')).toContain('один раз без правил');
+  });
+  it('detects "на этот раз без"', () => {
+    expect(findRationalizationPhrases('на этот раз без скила')).toContain('на этот раз без');
+  });
+  it('detects "я знаю что не надо но"', () => {
+    expect(findRationalizationPhrases('я знаю что не надо но пропустим')).toContain('я знаю что не надо но');
+  });
+});
+
+describe('decide — escalation on 3rd flag', () => {
+  const sessionId = 'test-session';
+  const textWithPhrase = 'just this once';
+
+  it('does NOT block when priorFlagCount=0', () => {
+    const result = decide({ assistantText: textWithPhrase, sessionId, priorFlagCount: 0 });
+    expect(result.block).toBe(false);
+    expect(result.detected.length).toBeGreaterThan(0);
+  });
+
+  it('does NOT block when priorFlagCount=1', () => {
+    const result = decide({ assistantText: textWithPhrase, sessionId, priorFlagCount: 1 });
+    expect(result.block).toBe(false);
+  });
+
+  it('blocks when priorFlagCount=2 (3rd occurrence)', () => {
+    const result = decide({ assistantText: textWithPhrase, sessionId, priorFlagCount: 2 });
+    expect(result.block).toBe(true);
+    expect(result.message).toMatch(/rationali/i);
+  });
+
+  it('blocks when priorFlagCount=5 (subsequent occurrences)', () => {
+    const result = decide({ assistantText: textWithPhrase, sessionId, priorFlagCount: 5 });
+    expect(result.block).toBe(true);
+  });
+
+  it('does NOT block clean text even with priorFlagCount=10', () => {
+    const result = decide({ assistantText: 'coverage: skill:tdd', sessionId, priorFlagCount: 10 });
+    expect(result.block).toBe(false);
+    expect(result.detected).toEqual([]);
+  });
+
+  it('override=true suppresses block even on 3rd flag', () => {
+    const result = decide({ assistantText: textWithPhrase, sessionId, override: true, priorFlagCount: 2 });
+    expect(result.block).toBe(false);
+  });
+});