[Nayira]

Summary

Defines a provider-neutral integration layer for optional connected-health imports, so imported values always record their source and timestamp, and users grant access one measurement type at a time.

Closes #202
Part of #151

Changes Made

• Added IntegrationConnection, which stores a user's explicit, read-only grant for one provider and a list of measurement types. allows(type) is the single permission check, and it is false for any type not granted or once the connection is disconnected.
• Added ImportedMeasurement, which requires provider, connection_id, unit and recorded_at, so a value without provenance cannot be saved.
• Added src/integrations.py with a provider registry (PROVIDERS) and an IntegrationAdapter protocol, so pages and endpoints never depend on provider-specific code. Apple Health and Health Connect are registered with plain-language limitations (neither has a web API).
• Added an INTEGRATIONS_ENABLED flag, off by default, so integrations stay optional and core features never depend on them.
• Added endpoints:
  • GET /api/v1/integrations/providers, which returns { enabled, providers }, with an empty providers list while the flag is off
  • GET /api/v1/users/me/connections, which lists the user's own connections and is not gated by consent or the flag, so users can always see what is connected
  • POST /api/v1/users/me/connections, which grants or replaces a connection and requires health consent and the flag
• Validation errors have clear codes: INTEGRATIONS_DISABLED, UNKNOWN_PROVIDER, UNSUPPORTED_MEASUREMENT_TYPE and VALIDATION_ERROR.
• Added docs/integrations.md covering principles, architecture, data model, permission rules, API and how to add a provider.

Testing

• Full backend test suite passed (75 tests), including 19 new integration tests covering:
  • the feature flag
  • authentication and health consent
  • unknown providers and unsupported types
  • re-granting
  • users only seeing their own connections
  • the permission check
  • required provenance fields
• The integration tests turn the flag off by default, so they pass whatever is set in a developer's local .env.

Checklist

• The code follows project conventions
• Documentation has been updated if needed
• No sensitive information is included
• Breaking changes are clearly documented
• Reviewers have enough context to review this PR

Additional Notes

• Backend only. There is no UI yet, and nothing changes for users while INTEGRATIONS_ENABLED is off, which is the default.
• No provider adapters are included. Reading Apple Health and Health Connect data belongs to the discovery and prototype issues under [Big Rock] Add optional connected-health integrations #151.
• No breaking changes. The two new collections are created on startup.

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud