Only regression tests: every one of them was checked to go red when the guard
it covers is reverted, and green again with it in place.
- a long error reaching the caller whole, and a half-built partition being
completed: both fail if the truncation in check() comes back
- a creation deferred while another session holds the advisory lock: fails if
the sequence no longer stops at the first deferral, since the partition
tracking is only updated by the last line of a sequence that ran to the end
- the classification of the outcomes a concurrent maintenance produces, with
the messages the fleets actually logged: fails if a signature is dropped
`addPartition` and the outcome classifier are exported to be reachable from
the tests, the advisory lock id gets a name so a test can hold the same lock,
and close() tolerates a driver whose partition factory was never started,
which is the driver shape the deferral test needs.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
