* fix(cloud): recalibrate the relay monitor's exhausted-retry freeze to a measured bar
The pre-drain dry-run froze at minute one on relayPostgresRetryExhausted: 0
in every run since #18521 reached the director, blocking the cell roll that
carries the same fix. #18521 made contended request-path waiters fail fast
(500 ms) instead of succeeding slowly, so exhaustion is now a steady
contention rate: 236/236 five-minute windows non-zero over 23 h; post-#18521
p50 42 / p90 147 / max 220 fleet-wide; the 2026-08-23 incident peaked at 467.
300 clears every measured healthy window and stays under the incident shape.
/v1/assign 503 share was unchanged by #18521 (13.9% vs 12.3%).
* test(cloud): pin the exhausted-retry freeze boundary at exactly 300
* docs(cloud): reword relay comments that still described the zero exhausted-retry bar
Phase 6 of the relay split: the relay's deploy/operate surface moves under cloud/ with 24 cloud-* workflows gated on ORCA_CLOUD_OPERATIONS_ENABLED, the Cloud SQL rollout lease action, the relay Terraform root (dual-accept identities for both repositories), scripts, docs, CODEOWNERS, and a terraform validate job in Cloud Verify.
Jinwoo Hong