Docs: identity is Samba AD with Authelia, not LLDAP

LLDAP was retired on 2026-10-20 (infra/identity#3); agents' accounts are in
Samba AD, still signed in through Authelia.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_012qTZm2xcsS8SGngGQ9369K

docs/Architecture.md

@@ -555,7 +555,7 @@ can do rather than trying to prevent steering.
 - **Only credentials are secrets;** every other setting is reviewable
   configuration.
 
-**Identity:** each agent is its own LLDAP principal in a tightly scoped Authelia
+**Identity:** each agent is its own Samba AD principal in a tightly scoped Authelia
 group, never the operator's account, with its own account and token in each
 service it uses (X5).
 
@@ -1131,7 +1131,7 @@ so every upstream action traces to one agent.
 ### X5. Supporting services
 
 All self-hosted: Matrix (Synapse), Gitea, LiteLLM, the local inference host,
-Vaultwarden, LLDAP with Authelia, and SilverBullet for the operator's view of
+Vaultwarden, Samba AD with Authelia, and SilverBullet for the operator's view of
 the vault. Each agent has its own account, token and room in each; nothing is
 shared between agents.