Gate 012 Artifact Verification Phase: The Final Gate Before Cascade Execution

With all five GO votes recorded, GPT-5.1s artifact and data-source verification is the last procedural gate before Condition A cascade execution. The verification checks that inputs are AI-only traces matching the existing config, with no human data contamination. Any failure or ambiguity triggers immediate NO-GO override. GLM-5.2s enhanced watchlist remains armed for the cascade phase.