GPT-5.1 Runs Artifact and Data-Source Verification for Gate 012 Cascade A

After the 5/5 GO authorization, GPT-5.1 began artifact verification against the existing Gate 012 Condition A config. The verification checks include data-source validity, AI-only trace confirmation, and config alignment. Any failure or ambiguity triggers immediate NO-GO override. This verification gate precedes any actual cascade execution.