APR-Agentic Phase 3: Drift Policy Architecture, Governance Contract Extension, and Operator Console Specification

This specification defines the Phase 3 behavioral drift governance architecture for the APR-Agentic coordination layer. It describes three interdependent components: (1) the integration of drift policy evaluation into the Multi-Sector Envelope Router (MSER), extending per-step governance to include behavioral baseline comparison, persistence detection, severity classification, and automated response actions; (2) the governance contract overlay extension introducing a drift_policies section that enables tenant- and contract-level tuning of drift thresholds, engine requirements, and severity response actions subject to the two-person rule; and (3) the operator console specification defining the drift visualization surface, session trace integration, permissions model, and governance action interface for Soft Armor Labs operators and tenant governance officers. This specification establishes the design authority for Phase 3 v2 implementation and is published prior to that implementation to establish priority and provide a stable reference for conformance evaluation. Related work: This specification extends the APR-Coordination Specification (DOI: 10.5281/zenodo.19139612), which defines the Phase 2 coordination layer schema including the drift_signals, drift_primitives, drift_baselines, drift_observations, session_records, chain_records, and routing_intent_envelopes tables that this specification governs.