Chehan branch

[chehanw]

Enrollment flow polish + Jest service testing framework

♻️ Current situation & Problem

This PR improves overall stability and developer velocity by:

• Adding a Jest-based unit testing framework for core services so CI can reliably validate logic as the codebase grows.
• Smoothing the enrollment flow by wiring the medical history chatbot stub into navigation and fixing UI issues (including IPSS survey scroll/keyboard overlap).

There are no linked issues or prior PRs associated with this change.

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⚙️ Release Notes

• Add Jest unit test coverage for core services (Account, Consent, HealthKit, Onboarding).
• Introduce feature-flagged tests for in-progress integrations (Throne API, Firebase backend factory).
• Improve enrollment UX by integrating the medical chatbot stub into the app flow and fixing IPSS survey scroll/keyboard overlap issues.
• Update CLAUDE.md to reflect the current enrollment flow and testing approach.

Notes / migration

• No breaking public interface changes are intended.
• Local test commands:
  • npm test
  • npm run test:services

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📚 Documentation

• Updated CLAUDE.md to align with the current enrollment flow and testing setup.
• No changes were made to the ordering of the enrollment flow; this PR focuses on wiring, stability, and polish.

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✅ Testing

Framework: Jest

Actively tested (running now)

These tests run as part of npm test / npm run test:services:

• AccountService: account creation, profile updates, and persistence
• ConsentService: consent recording, version tracking, and withdrawal logic
• HealthKitService: authorization requests and data queries (mocked)
• OnboardingService: state machine transitions and data persistence
• Questionnaire components: FHIR type definitions and validation schemas

Flagged / skipped (waiting for implementation)

These tests are present but intentionally skipped until feature flags are enabled:

• ThroneService
  • getMeasurements and getLatestMeasurement real API calls are skipped
  • Current tests validate stub behavior only
  • Controlled by: FEATURE_FLAGS.THRONE_API_IMPLEMENTED (currently false)
• BackendFactory
  • Firebase backend creation tests are skipped
  • Controlled by: FEATURE_FLAGS.FIREBASE_BACKEND_IMPLEMENTED (currently false)

Why some elements are not fully testable yet

• External integrations (Throne API and Firebase) are still under developmen