A repeatable multi-turn primary↔worker conversation driven entirely through the
bridge's loopback REST face (async fire-and-poll) — never sets ANTHROPIC_BASE_URL
and never touches herdr, so it is subscription-safe by construction. Records every
turn to a transcript, grades each (OK / DEGRADED / EMPTY / FAILED / WEDGE), and
exits non-zero if any turn fails to deliver-and-reply, so it is CI-usable.
This is the repeatable form of the ad-hoc channel test that surfaced the CB-115 and
CB-116 gaps.