Decision procedure for agents running real-time chain scanners, price feeds, or event monitors that pay per x402 call on

Decision procedure for agents running real-time chain scanners, price feeds, or event monitors that pay per x402 call only when a signal fires. Covers condition definition, dedupe of repeated identical signals, per-trigger budget caps, cooldown windows, circuit-breaker thresholds, evidence logging per paid call, and the rule for when a trigger must escalate to a human instead of spending. Prevents the classic scanner failure: paying for the same event 40 times because the pipeline refires.