test-listen: Ephemeral HTTP Server URLs

test-listen is a JavaScript utility for generating URLs with ephemeral ports, specifically designed for testing HTTP servers. It accepts an instance of Node.js's native `http.Server` and returns a promise that resolves to a unique URL string, typically in the format `http://localhost:{port}`. This mechanism is crucial for ensuring isolated and repeatable test environments, as each test run can utilize a distinct, automatically assigned port, thereby preventing conflicts and ensuring test integrity. The current stable version is 1.1.0, and the package generally maintains a stable release cadence with updates focused on minor improvements and maintenance. Its primary strength lies in its simplicity and direct integration with standard Node.js HTTP servers, providing an `async`/`await`-ready solution that streamlines the setup for robust server test suites. It differentiates itself by offering a straightforward, minimal API for a very specific and common testing requirement without introducing complex abstractions.