Create imperative / `AutoClosable` version

Basically a version without the `block` part, that instead returns an `AutoClosable`. Also perhaps supports attaching to a `CoroutineScope`.

Start by reading the existing block-based hook API and the project documentation to understand its lifecycle and coroutine behavior. Define the imperative AutoClosable API and clarify whether CoroutineScope support is part of the required change; done means the new usage is documented and covered by tests for normal completion, failure, and application shutdown.

Written by the indexing model from the issue text.