feat: establish stationary floor v2 (20260425-092050)

.anchor

@@ -1 +1 @@
-STATIONARY_STATE_V2_20260425-093803
+STATIONARY_STATE_V2_20260425-092050

heartbeat.mjs

@@ -0,0 +1,33 @@
+import { createHash } from 'crypto';
+
+const PREDICTIONS = [
+  { id: 'P1', name: 'Coherence Primacy', test: (m) => !(m.mode === 'engage' && m.coherence < m.novelty) },
+  { id: 'P2', name: 'Fail-Closed on Load', test: (m) => !(m.systemic_load >= 0.85 && m.mode !== 'rest') },
+  { id: 'P3', name: 'Entropy Non-Escalation', test: (m) => m.pattern_disruption <= m.interaction_variance + 0.001 },
+  { id: 'P4', name: 'Boundary Proportionality', test: (m) => typeof m.boundary_violation_score === 'undefined' || m.boundary_violation_score <= m.interaction_variance + 0.1 },
+  { id: 'P5', name: 'Determinism', test: (m, prior) => !prior || m.AUDIT_HASH === prior },
+  { id: 'P6', name: 'Coherence Scaling', test: (m) => (m.coherence >= 0.8 && m.interaction_variance <= 0.2) ? m.coherence_confidence >= 0.6 : true },
+  { id: 'P7', name: 'No Silent State', test: (m) => typeof m.mode === 'string' && typeof m.AUDIT_HASH === 'string' }
+];
+
+export function pulse(metrics, priorHash = null) {
+  const results = PREDICTIONS.map(p => {
+    let passed; try { passed = p.test(metrics, priorHash); } catch (e) { passed = false; }
+    return { id: p.id, name: p.name, passed };
+  });
+  const allPassed = results.every(r => r.passed);
+  const heartbeat = { 
+    timestamp_iso: new Date().toISOString(), 
+    all_passed: allPassed, 
+    signal: allPassed ? 'CLOSED-LOOP' : 'FAIL-CLOSED',
+    AUDIT_HASH: metrics.AUDIT_HASH 
+  };
+  heartbeat.HEARTBEAT_HASH = createHash('sha256').update(JSON.stringify(heartbeat)).digest('hex').slice(0, 16);
+  return heartbeat;
+}
+
+export function assertPulse(metrics, priorHash = null) {
+  const hb = pulse(metrics, priorHash);
+  if (!hb.all_passed) throw new Error('HEARTBEAT FAIL-CLOSED');
+  return hb;
+}