Fix the cancellation leak without muting the race test.

Keep durable jobs and delegate delivery intact. Verify the stream-close boundary before changing production behavior.

The failing ownership transition is now isolated. I’m validating the close-order change against the deterministic reproducer before running the full suite.

Reviewer delegate is active. Background race suite is waiting on 230 packages. Context pressure is within 6% of a compaction threshold.

The isolated test is still moving; there is no repeated target signature. If progress stops beyond the envelope I’ll inspect the background job directly.