Record the firewall as live on the PoC

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>

BACKLOG.md

@@ -29,8 +29,10 @@ A8, A9. **Left:**
 - From A8: thread ids are bounded and documented as project-wide, but not
   scoped per user; Python engines are resolved with an explicit PyTorch
   index and a PEP 751 lock, but locks are not shipped per engine version.
-- A9's ruleset is unit-tested and its syntax checked with `nft -c` on a
-  PoC machine; it has not yet been applied to a live machine.
+- A9 is live on the PoC (140, 149, 150, 148): llmgw's ports answer
+  10.0.0.0/24, are dropped from outside it (tested over IPv6), and ssh,
+  :8080 and other services are untouched. The other nodes get it on their
+  next `node add`.
 
 ### A1. Toolchain (S, hours)
 `govulncheck` finds 11 standard-library vulnerabilities reachable from this