Kotlin/kotlinx.coroutines ? reverse-engineered prompt

Build me a Kotlin coroutines library that gives developers a simple way to do async work without blocking threads, with support for launch, async, delay, structured concurrency, cancellation, Flow streams, channels, mutexes, semaphores, and dispatcher support for background and UI work. It should work across platforms, not just on the JVM, and include the extra pieces for testing, debugging, and integrating with common reactive or future based APIs. I’d also like clear examples and docs showing how to use it in real apps, especially for UI code and for testing suspending functions. If some parts depend on current Kotlin or platform docs, look them up online and follow the latest guidance. Keep the API clean and consistent with how coroutines are normally used in Kotlin, and make sure the project builds and the examples run.