* Drop peer services if their cancel handles are dropped
* Exit the client task if the heartbeat task exits
* Allow multiple errors on a connection without panicking
* Explain why we don't need to send an error when the request is cancelled
* Document connection fields
* Make sure connections don't hang due to spurious timer or channel usage
* Actually shut down the client when the heartbeat task exits
* Add tests for unready services
* Close all senders to peer when `Client` is dropped
* Return a Client error if the error slot has an error
* Add tests for peer Client service errors
* Make Client drop and error cleanups consistent
* Use a ClientDropped error when the Client struct is dropped
* Test channel and error state in peer Client tests
* Move all Connection cleanup into a single method
* Add tests for Connection
* fix typo in comment
Co-authored-by: Conrado Gouvea <conrado@zfnd.org>
Co-authored-by: Conrado Gouvea <conrado@zfnd.org>
Co-authored-by: Alfredo Garcia <oxarbitrage@gmail.com>