Koa User-Agent Detection Middleware

koa-useragent is a Koa.js middleware designed for detecting and parsing user-agent strings from incoming HTTP requests. It enriches the Koa context (`ctx`) with a `userAgent` object containing detailed information such as browser, OS, device type (mobile, desktop, bot), and version. The package is currently at version `4.1.0`, released in July 2022, and appears to maintain an active development status, although major version releases have slowed since 2020. Key differentiators include its tight integration with Koa's context, providing structured user-agent data directly for use in middleware and route handlers, and its robust TypeScript support, which has been a focus since version 2.1.0 and refined in subsequent major releases. It is built upon the well-established `useragent` library for reliable parsing.