Oracle wave-4 watch-outs: - '5xx count: 1 should not be hidden' - 'Add one future regression check that fails if both primary and fallback LLM paths fail, since the fallback tunnel is now part of the live behavior' E2E now reports llm-gateway 5xx and system 5xx as two distinct counts. The canvas-primary 503 is acknowledged + counted; only system 5xx must be zero. New no_system_5xx assertion guards that. wave4 adds gap1_cascade_did_not_exhaust: fails if telemetry shows '[llm] all gateways exhausted' on the live assistant path. Locks in that at least one gateway (primary or fallback-dev) is returning real model output.