Implement Phase 8: Testing & Deployment

Testing Infrastructure:
- Configure Jest with Next.js integration and TypeScript support
- Add React Testing Library with proper setup for Next.js components
- Install and configure Playwright for E2E testing
- Create jest.setup.ts with mocks for Next.js router and browser APIs
- Add CSS module mocking with identity-obj-proxy

Unit Tests:
- Create LoadingFallback component tests covering all 5 variants
- Create tracking API tests for data transformation logic
- Test createActivity, getActivities data structure conversions
- Verify frontend (timestamp/data) to backend (startedAt/metadata) mapping

E2E Tests (Playwright):
- Create comprehensive tracking flow tests
- Test navigation to all tracker pages (feeding, sleep, diaper)
- Test homepage Today's Summary display
- Test AI Assistant and Analytics navigation
- Test feeding, sleep, and diaper tracker UI elements
- Configure multi-browser testing (Chrome, Firefox, Safari, Mobile)

CI/CD Pipeline (GitHub Actions):
- Create automated CI/CD workflow for master/main branches
- Run linting on every push and PR
- Execute unit tests with coverage reporting
- Run E2E tests (Chromium) in CI environment
- Build application and upload artifacts
- Upload test coverage to Codecov
- Upload Playwright test reports as artifacts

Test Scripts:
- npm test: Run Jest unit tests
- npm run test⌚ Run tests in watch mode
- npm run test:coverage: Generate coverage report
- npm run test:e2e: Run Playwright E2E tests
- npm run test:e2e:ui: Run E2E tests with UI mode
- npm run test:e2e:headed: Run E2E tests in headed mode

Documentation:
- Create comprehensive testing guide (tests/README.md)
- Document test structure and best practices
- Add troubleshooting section for common issues
- Include useful commands for debugging tests

Coverage Thresholds:
- Branches: 70%
- Functions: 70%
- Lines: 70%
- Statements: 70%

🤖 Generated with [Claude Code](https://claude.com/claude-code)

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

maternal-web/lib/api/__tests__/tracking.test.ts

@@ -0,0 +1,104 @@
+import { trackingApi } from '../tracking'
+import apiClient from '../client'
+
+jest.mock('../client')
+
+const mockedApiClient = apiClient as jest.Mocked<typeof apiClient>
+
+describe('trackingApi', () => {
+  beforeEach(() => {
+    jest.clearAllMocks()
+  })
+
+  describe('createActivity', () => {
+    it('transforms frontend data to backend format', async () => {
+      const mockActivity = {
+        id: 'act_123',
+        childId: 'chd_456',
+        type: 'feeding',
+        startedAt: '2024-01-01T12:00:00Z',
+        metadata: { amount: 120, type: 'bottle' },
+        loggedBy: 'usr_789',
+        createdAt: '2024-01-01T12:00:00Z',
+      }
+
+      mockedApiClient.post.mockResolvedValue({
+        data: { data: { activity: mockActivity } },
+      } as any)
+
+      const result = await trackingApi.createActivity('chd_456', {
+        type: 'feeding',
+        timestamp: '2024-01-01T12:00:00Z',
+        data: { amount: 120, type: 'bottle' },
+      })
+
+      expect(mockedApiClient.post).toHaveBeenCalledWith(
+        '/api/v1/activities?childId=chd_456',
+        {
+          type: 'feeding',
+          startedAt: '2024-01-01T12:00:00Z',
+          metadata: { amount: 120, type: 'bottle' },
+          notes: undefined,
+        }
+      )
+
+      expect(result).toEqual({
+        ...mockActivity,
+        timestamp: mockActivity.startedAt,
+        data: mockActivity.metadata,
+      })
+    })
+  })
+
+  describe('getActivities', () => {
+    it('transforms backend data to frontend format', async () => {
+      const mockActivities = [
+        {
+          id: 'act_123',
+          childId: 'chd_456',
+          type: 'feeding',
+          startedAt: '2024-01-01T12:00:00Z',
+          metadata: { amount: 120 },
+        },
+        {
+          id: 'act_124',
+          childId: 'chd_456',
+          type: 'sleep',
+          startedAt: '2024-01-01T14:00:00Z',
+          metadata: { duration: 120 },
+        },
+      ]
+
+      mockedApiClient.get.mockResolvedValue({
+        data: { data: { activities: mockActivities } },
+      } as any)
+
+      const result = await trackingApi.getActivities('chd_456', 'feeding')
+
+      expect(mockedApiClient.get).toHaveBeenCalledWith('/api/v1/activities', {
+        params: { childId: 'chd_456', type: 'feeding' },
+      })
+
+      expect(result).toEqual([
+        {
+          id: 'act_123',
+          childId: 'chd_456',
+          type: 'feeding',
+          startedAt: '2024-01-01T12:00:00Z',
+          metadata: { amount: 120 },
+          timestamp: '2024-01-01T12:00:00Z',
+          data: { amount: 120 },
+        },
+        {
+          id: 'act_124',
+          childId: 'chd_456',
+          type: 'sleep',
+          startedAt: '2024-01-01T14:00:00Z',
+          metadata: { duration: 120 },
+          timestamp: '2024-01-01T14:00:00Z',
+          data: { duration: 120 },
+        },
+      ])
+    })
+  })
+})