- Added configuration options for Stalwart hosted mail in .env.example.
- Updated Docker Compose to include Stalwart service with health checks.
- Introduced new API endpoints for managing mail domains and migration projects.
- Enhanced Authentik blueprints for user enrollment and post-migration security.
- Updated OAuth handling for Google and Microsoft migration processes.
- Improved error handling and response structures in the mail API.
- Added integration tests for email claiming and migration workflows.
- Introduced a new `.env.test.example` file for integration test configuration.
- Added a `Makefile` to streamline test commands for unit and integration tests.
- Implemented an integration testing harness with support for PostgreSQL, MinIO, and Redis using testcontainers.
- Created a suite of integration tests covering health checks and user management functionalities.
- Enhanced CI workflow to include integration tests with necessary environment variables.
