- Introduced `pyproject.toml` to centralize backend tool configurations (e.g., Ruff, mypy, coverage, pytest).
- Replaced Black, isort, and Flake8 with Ruff for linting, formatting, and import sorting.
- Updated `requirements.txt` to include Ruff and remove replaced tools.
- Added `Makefile` to streamline development workflows with commands for linting, formatting, type-checking, testing, and cleanup.
- **Security Headers:** Add tests for HSTS in production, CSP in strict mode, and root endpoint response types.
- **Permissions:** Introduce tests for critical security paths, including superuser bypass and edge case scenarios.
- **CRUD Testing Enhancements:** Cover error scenarios for soft deletes, restores, and eager loading with SQLAlchemy options.
- **Organization Routes:** Validate user organization endpoints for memberships, details, and member listings.
- Add defensive code comments with `# pragma: no cover` for unreachable code sections.
- Introduced comprehensive tests for session CRUD error cases, covering exception handling, rollback mechanics, and database failure propagation.
- Added robust API error handling tests for admin routes, including user and organization management.
- Enhanced test coverage for unexpected errors, edge cases, and validation flows in session and admin operations.
- Introduced new unit tests for session CRUD operations, including `update_refresh_token`, `cleanup_expired`, and multi-user session handling.
- Added comprehensive tests for `CRUDBase` methods, covering edge cases, error handling, and UUID validation.
- Reduced default test session creation from 5 to 2 for performance optimization.
- Enhanced pagination, filtering, and sorting validations in `get_multi_with_total`.
- Improved error handling with descriptive assertions for database exceptions.
- Introduced tests for eager-loaded relationships in user sessions for comprehensive coverage.
