Koa Response Time Middleware

koa-response-time is a minimal Koa middleware designed to automatically add an `X-Response-Time` header to HTTP responses. This header indicates the duration it took for the Koa application to process and respond to a request. Currently at version 2.1.0, which was last published over 7 years ago, the package is highly stable and in maintenance mode, with no anticipated new feature development. Its primary differentiator is its simplicity and direct integration into the Koa ecosystem, providing a standard and unobtrusive way to measure request-response cycles. It supports high-resolution timing via an optional `hrtime` configuration for more precise measurements. The package has no external runtime dependencies, ensuring a lean footprint.