Express Service Readiness Middleware

This module provides Express.js middleware for determining whether server routes should be exposed based on the health status of critical service dependencies. Currently stable at version 1.0.25, the package is typically updated for bug fixes and compatibility with new Express.js versions. A key differentiator is its focus on *readiness* at startup rather than continuous *liveness* monitoring. Once the service achieves a 'ready' state, it maintains this status for its lifetime, meaning subsequent failures of critical dependencies will *not* revert it to an 'unready' state and block non-whitelisted routes. It returns a 502 status code for non-whitelisted routes when critical dependencies are not ready, and allows specific paths to be whitelisted for access even during unready periods. It distinguishes between critical and non-critical dependencies, allowing flexible health definitions.