Replace the bare `except BaseException: pass` in the `teardown` closure
with a `warn()` call that includes the container name and operation type
("compose-down"), so cleanup failures are visible in the log rather than
silently discarded. Non-blocking: the exception is consumed and teardown
continues, preserving the original error-propagation contract.
Add test_docker_launch_teardown.py to lock the new behaviour: it injects
a RuntimeError via a mocked `compose_down` callback and asserts the
WARNING message contains the container name and operation label.
didericis-claude