Codex Stage 2.6A-FIX QT001 Audit

Status COMPLETE STAGE2_6A_FIX_FAIL_HARDCODE_STILL_DANGEROUS. Do not proceed 2.6B. Policy/hardcode partly relocated into rules/signals/signoff. MCP upload/readback PASS for 14 docs. Post-upload no-worse: birth_registry 1,210,985 (+14 audit births), targets 8, QT001 origin 0, permits 0, done 0, readiness BLOCKED, hardcode guard FAIL, cross-layer 9/9.