45h0kg/zk-proof-gateway ? reverse-engineered prompt

Build me a working prototype of this zero knowledge proof gateway for agent to agent order checks.

I want an app where one agent can submit an order without revealing the actual order value, and the gateway only learns whether it passes a governance rule like order notional is within a pre trade cap. Please include a demo flow that shows a governance tool for signing and verifying predicates, a prover and a gateway, a simple audit log that chains entries together, and an end to end example where a compliant order is allowed, a missing proof is denied, a tampered proof is denied, and a replayed proof is rejected.

If it makes sense, wire it up so the gateway and prover can run as separate services, and make the proof verification fast. A small HTTP based demo is fine. Also include a basic command that runs the full example and tests. Look up current docs online if you need to.