feat: certify codegen chat drafts through loop

docs/plans/CASAN_PLAN_13_NEXT_STEPS.puml

@@ -23,11 +23,12 @@ package "DONE - Plan 13 Control Panel" #E8F5E9 {
   component "Command Center baseline\n9 evidence-backed widgets\nbriefing + ticker + evidence drawer" as command_done #D5F5E3
   component "Loop/Chat widget\nbudget + replay drawer + chat ticker\nextends Command Center contract" as loop_widgets_done #D5F5E3
   component "Approvals escalation\nturn ESCALATED -> inbox\nJWT + SoD + reason" as approvals_done #D5F5E3
+  component "CODEGEN-as-loop\nH4 guarded codegen\nloop-certified artifacts" as codegen_done #D5F5E3
 }
 
 package "NEXT - offline platform follow-ups" #FFF8E1 {
   component "RAI / Data Gov view\nretention + model-card + PII report" as rai #F9E79F
-  component "CODEGEN-as-loop\nH4 guarded codegen\nloop-certified artifacts" as codegen_loop #F9E79F
+  component "Chat multi-tenant hardening\nper-tenant state + quotas + crypto" as chat_mt #F9E79F
 }
 
 package "EXTERNAL / MANAGED PROD" #FDEDEC {
@@ -44,10 +45,11 @@ api_done --> command_done : GET /api/v1/command
 command_done --> gov_core : provenance + audit state
 loop_widgets_done --> command_done : specialized widget
 approvals_done --> gov_core : proposals + SoD
+codegen_done --> gov_core : guarded loop-run
 
 lead --> rai : next if staying offline
 rai --> gov_core : read RAI + policy artifacts
-codegen_loop --> gov_core : guarded loop-run
+chat_mt --> gov_core : tenant boundaries
 
 managed_oidc ..> local_prod : replace mock IdP/cert
 alerts ..> gov_core : route real incidents
@@ -55,7 +57,7 @@ billing ..> command_done : ground-truth FinOps
 
 note right of rai
 Recommended next:
-1. If no external infra: build RAI view or Plan-18 CODEGEN slice.
+1. If no external infra: build RAI view or Plan-18 tenant hardening.
 2. If infra is available: promote local-prod OIDC to managed prod.
 3. Keep chat widgets on the existing Command envelope.
 4. Keep every metric evidence-backed with provenance.