06 — Stage 1 Implementation Readiness (Supertrack F)

Deliverable: knowledge/dev/architecture/BIRTH_STAGE1_GATEWAY_SSOT_IMPLEMENTATION_PACKET.md (authored; no implementation performed).

The packet specifies, so the next T1 macro needs no rediscovery:

• Immutable gateway release: extract fn_birth_policy_decision / fn_birth_resolve_identity / fn_birth_register from the current guarded fn_birth_registry_auto (norm-md5 c022f849…) into a versioned Git migration; rewrite the realtime trigger as a thin wrapper.
• Runtime semantic contract registry: append-only birth_gateway_contract table + verifier wired into v_birth_gateway_ssot_drift_detector (replacing Stage 0's baked baseline).
• Setup DOT remediation: strip CREATE OR REPLACE FUNCTION from dot-birth-trigger-setup (reconcile-only) and dot-birth-auto_certify from dot-schema-birth-registry-ensure; restore quarantine only after review.
• Permit + ledger: birth_admission_permit + birth_backfill_ledger (both currently absent) — QT-001 apply fails closed without an open permit.
• Prerequisites: resolve the 43 unclassified BIRTH_REQUIRED identities; create/reclassify the 2 missing tables.
• Migration file list, 5 teeth tests (T1 install-old-fn→guard-FAIL→rollback proven feasible), rollback, exact no-go, T2 checklist.

Entry preconditions (all currently true): gateway guard PASS, drift OK, 2/2 frozen.

Completion: next T1 macro can implement Stage 1 directly from the packet.