11 — Design Index Update

knowledge/dev/architecture/BIRTH_GATEWAY_DESIGN_INDEX.md updated rev19 → rev21:

• Added top banner: Stage 2.6A-FIX5 PARTIAL (rev20) — recursive structural callgraph; legacy planner v2 removed from the real path; false proofs rebuilt; ready for Codex re-audit.
• Added top banner: Codex independent audit of FIX4 = FAIL (STAGE2_6A_FIX4_FAIL_HARDCODE_OR_BYPASS_STILL_DANGEROUS) with the 12 blockers.
• Added macro-table rows: 2.6A-FIX4 (PARTIAL, later failed re-audit), 2.6A-FIX4-codex (FAIL), 2.6A-FIX5 (PARTIAL; apply BLOCKED).
• Re-audit-required and "no 2.6B until Codex PASS" stated in both the FIX5 banner and the FIX5 table row.

Status line intent preserved: Stage 2 PARTIAL; QT-001 apply BLOCKED; fresh independent Codex re-audit gating 2.6B.