Read ECF Evaluation Lab preview metadata

Owner/admin metadata for the ECF Evaluation Lab preview route. Returns accepted schemas, advisory dimensions, evidence methods, required route-phase evidence, and an advisory-only authority boundary. It performs no DB writes, public badge creation, public route creation, Router trust mutation, marketplace verification mutation, Seller OS trust mutation, AgentCore/x402 readiness mutation, deployment approval, capability or scorecard publication, certification claim creation, provider calls, memory approval, production-readiness override, or private Full ECF exposure.