ResourcesNotReleased

Tearing a session down did not release everything cleanly.

Teardown runs every close in its own runCatching so that one failure cannot strand the resources after it, which is right. What was wrong is that the failures then vanished: a decoder or device that refused to close left no trace anywhere, and the next open met a machine in a state nothing had reported. The session is gone either way, which is why this is a warning and not a failure, but it is now a warning that exists.