Haraka Test Fixtures

The `haraka-test-fixtures` package provides a comprehensive set of mock objects and utilities specifically designed for testing Haraka SMTP server plugins and core components. It enables developers to create isolated test environments by simulating key Haraka abstractions such as `Connection`, `Transaction`, `Plugin`, `Logger`, and `Results` objects without the overhead of running a full Haraka server. This allows for focused unit and integration testing of plugin logic. The current stable version is 1.4.1, released with bug fixes and dependency updates. Releases follow an ad-hoc schedule, primarily driven by maintenance requirements, synchronization with the main Haraka project, and dependency bumps. Its key differentiator lies in its deep integration and direct analogy to Haraka's internal architecture, providing tailor-made testing primitives that generic mocking libraries cannot easily replicate. It helps abstract away the complexities of Haraka's lifecycle for efficient plugin development and testing.