When create_bridge_network or compose-up raised mid-deploy, the
deployer marked the topology FAILED and re-raised — but left every
network it had already created alive. The next deploy attempt tripped
over the orphans with 'Pool overlaps with other one on this address
space' (IPAM conflict).
Track networks created in the current attempt; on exception, tear down
the started compose stack (if any), remove the networks in reverse
order, and delete the compose file before marking FAILED. Rollback
errors are logged but never mask the original failure.
Covered by a new regression test that drives a docker client which
succeeds once then raises, and asserts every created network is also
removed.
test_compose asserts the new decnet.topology.* labels land on both base
deckies (role=base, no service marker) and service fragments
(service=true). The stub docker client in test_deploy grew a filters
kwarg so it keeps matching the real .networks.list(filters=...) call
signature now used by the deployer.
Covers dry-run compose emission (no status change), FAILED transition
with reason logged on daemon errors, teardown from FAILED, and a
live-marked end-to-end test that creates/removes bridge networks
against a real docker daemon (skipped on CI).
