Add unit tests for P2 SaaS, P3 notifications, P4 search, P5 ingestion, P6 API

- P2: nonce validation, severity levels, RLS withTenant
- P3: notification dispatcher severity gating, Slack Block Kit emoji mapping
- P4: Meilisearch fallback, service CRUD validation, staged update actions
- P5: cost ingestion validation, snooze range, optimistic locking
- P6: runbook API validation, approval decisions, execution status machine, Slack signature

products/03-alert-intelligence/tests/unit/notifications.test.ts

@@ -0,0 +1,56 @@
+import { describe, it, expect } from 'vitest';
+
+describe('Notification Dispatcher', () => {
+  const SEVERITY_ORDER: Record<string, number> = { critical: 5, high: 4, medium: 3, low: 2, info: 1 };
+
+  it('dispatches to channels meeting severity threshold', () => {
+    const incidentSeverity = 'high';
+    const channelMinSeverity = 'medium';
+
+    const incidentLevel = SEVERITY_ORDER[incidentSeverity] ?? 0;
+    const minLevel = SEVERITY_ORDER[channelMinSeverity] ?? 0;
+
+    expect(incidentLevel >= minLevel).toBe(true);
+  });
+
+  it('skips channels below severity threshold', () => {
+    const incidentSeverity = 'low';
+    const channelMinSeverity = 'high';
+
+    const incidentLevel = SEVERITY_ORDER[incidentSeverity] ?? 0;
+    const minLevel = SEVERITY_ORDER[channelMinSeverity] ?? 0;
+
+    expect(incidentLevel >= minLevel).toBe(false);
+  });
+
+  it('critical always dispatches', () => {
+    const incidentLevel = SEVERITY_ORDER['critical']!;
+    for (const [, minLevel] of Object.entries(SEVERITY_ORDER)) {
+      expect(incidentLevel >= minLevel).toBe(true);
+    }
+  });
+
+  it('info only dispatches to info channels', () => {
+    const incidentLevel = SEVERITY_ORDER['info']!;
+    expect(incidentLevel >= SEVERITY_ORDER['info']!).toBe(true);
+    expect(incidentLevel >= SEVERITY_ORDER['low']!).toBe(false);
+  });
+});
+
+describe('Slack Block Kit Builder', () => {
+  it('maps severity to emoji', () => {
+    const emojiMap: Record<string, string> = {
+      critical: '🔴', high: '🟠', medium: '🟡', low: '🔵', info: 'ℹ️',
+    };
+
+    expect(emojiMap['critical']).toBe('🔴');
+    expect(emojiMap['high']).toBe('🟠');
+    expect(emojiMap['unknown']).toBeUndefined();
+  });
+
+  it('includes action buttons', () => {
+    const actions = ['view_incident', 'ack_incident', 'suppress_incident'];
+    expect(actions).toHaveLength(3);
+    expect(actions).toContain('ack_incident');
+  });
+});