fix(vv): resolve all 6 V&V issues — field trial unblocked

All findings from the inaugural LeadValidator audit resolved and
confirmed. Release gate: PASS.

VV_ISSUE_002 (BLOCKER): 15 OpenAPI specs verified present covering
all 20 route groups (46 endpoints documented in docs/openapi/)

VV_ISSUE_003 (MAJOR): Remove any types from src/db/pool.ts —
replaced pool.query shim with unknown[] + Object.defineProperty,
zero any types, eslint-disable suppressions removed

VV_ISSUE_004 (MAJOR): Remove raw Pool from ScaffoldController and
HealthDetailedController — injected AgentRepository/CredentialRepository
and DbProbe interface respectively; added CredentialRepository.findActiveClientId()

VV_ISSUE_005 (MAJOR): Add unit tests for 5 untested services —
ComplianceStatusStore, EventPublisher, MarketplaceService,
OIDCTrustPolicyService, UsageService

VV_ISSUE_006 (MAJOR): Add integration tests for 7 missing route
groups — analytics, billing, tiers, webhooks, marketplace,
oidc-trust-policies, oidc-token-exchange

VV_ISSUE_001 (MINOR): Create missing design.md and tasks.md in 4
OpenSpec archives — all archives now complete

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

tests/unit/services/UsageService.test.ts

@@ -0,0 +1,116 @@
+/**
+ * Unit tests for src/services/UsageService.ts
+ */
+
+import { Pool } from 'pg';
+import { UsageService } from '../../../src/services/UsageService';
+
+jest.mock('pg');
+
+const MockPool = Pool as jest.MockedClass<typeof Pool>;
+
+function makePool(): jest.Mocked<Pool> {
+  const pool = new MockPool() as jest.Mocked<Pool>;
+  pool.query = jest.fn();
+  return pool;
+}
+
+const TENANT_ID = 'org-abc-123';
+const DATE = '2026-04-07';
+
+describe('UsageService', () => {
+  let service: UsageService;
+  let pool: jest.Mocked<Pool>;
+
+  beforeEach(() => {
+    jest.clearAllMocks();
+    pool = makePool();
+    service = new UsageService(pool);
+  });
+
+  describe('getDailyUsage()', () => {
+    it('should return usage summary with real api call count', async () => {
+      pool.query = jest.fn()
+        .mockResolvedValueOnce({ rows: [{ count: '42' }], rowCount: 1 })
+        .mockResolvedValueOnce({ rows: [{ count: '5' }], rowCount: 1 });
+
+      const result = await service.getDailyUsage(TENANT_ID, DATE);
+
+      expect(result.tenantId).toBe(TENANT_ID);
+      expect(result.date).toBe(DATE);
+      expect(result.apiCalls).toBe(42);
+      expect(result.agentCount).toBe(5);
+    });
+
+    it('should default apiCalls to 0 when no usage row exists', async () => {
+      pool.query = jest.fn()
+        .mockResolvedValueOnce({ rows: [{ count: '0' }], rowCount: 1 })
+        .mockResolvedValueOnce({ rows: [{ count: '3' }], rowCount: 1 });
+
+      const result = await service.getDailyUsage(TENANT_ID, DATE);
+
+      expect(result.apiCalls).toBe(0);
+    });
+
+    it('should handle missing count row gracefully (defaults to 0)', async () => {
+      pool.query = jest.fn()
+        .mockResolvedValueOnce({ rows: [], rowCount: 0 })
+        .mockResolvedValueOnce({ rows: [{ count: '2' }], rowCount: 1 });
+
+      const result = await service.getDailyUsage(TENANT_ID, DATE);
+
+      expect(result.apiCalls).toBe(0);
+    });
+
+    it('should query usage_events with correct tenant and date params', async () => {
+      pool.query = jest.fn()
+        .mockResolvedValueOnce({ rows: [{ count: '10' }], rowCount: 1 })
+        .mockResolvedValueOnce({ rows: [{ count: '0' }], rowCount: 1 });
+
+      await service.getDailyUsage(TENANT_ID, DATE);
+
+      expect(pool.query).toHaveBeenNthCalledWith(
+        1,
+        expect.stringContaining('usage_events'),
+        [TENANT_ID, DATE],
+      );
+    });
+  });
+
+  describe('getActiveAgentCount()', () => {
+    it('should return the count of non-decommissioned agents', async () => {
+      pool.query = jest.fn().mockResolvedValue({ rows: [{ count: '7' }], rowCount: 1 });
+
+      const count = await service.getActiveAgentCount(TENANT_ID);
+
+      expect(count).toBe(7);
+    });
+
+    it('should return 0 when no agents exist for tenant', async () => {
+      pool.query = jest.fn().mockResolvedValue({ rows: [{ count: '0' }], rowCount: 1 });
+
+      const count = await service.getActiveAgentCount(TENANT_ID);
+
+      expect(count).toBe(0);
+    });
+
+    it('should exclude decommissioned agents (query contains status check)', async () => {
+      pool.query = jest.fn().mockResolvedValue({ rows: [{ count: '3' }], rowCount: 1 });
+
+      await service.getActiveAgentCount(TENANT_ID);
+
+      expect(pool.query).toHaveBeenCalledWith(
+        expect.stringContaining('decommissioned'),
+        [TENANT_ID],
+      );
+    });
+
+    it('should handle missing count row gracefully', async () => {
+      pool.query = jest.fn().mockResolvedValue({ rows: [], rowCount: 0 });
+
+      const count = await service.getActiveAgentCount(TENANT_ID);
+
+      expect(count).toBe(0);
+    });
+  });
+});