chore(spec): archive completed billing hardening

.kiro/specs/billing-post-usage-correctness-hardening/spec.json → .kiro/specs/archive/billing-post-usage-correctness-hardening/spec.json

@@ -1,9 +1,10 @@
 {
   "feature_name": "billing-post-usage-correctness-hardening",
   "created_at": "2026-08-16T15:42:00+02:00",
-  "updated_at": "2026-08-16T21:08:51+02:00",
+  "updated_at": "2026-08-17T08:32:59+02:00",
   "language": "en",
-  "phase": "tasks-generated",
+  "phase": "completed",
+  "status": "completed",
   "approvals": {
     "requirements": {
       "generated": true,
@@ -18,6 +19,7 @@
       "approved": true
     }
   },
-  "ready_for_implementation": true,
+  "ready_for_implementation": false,
+  "completed": true,
   "project_description": "Correct and harden the post-usage billing architecture merged in PR #340 without reopening the broader simplification refactor: preserve actual B-leg ordering, settle against the correct backend/model customer rate card, make customer settlement independent from provider-cost catalog readiness, and bound all runtime billing-call state to the lifetime of one BillingCallID."
 }

.kiro/specs/billing-post-usage-correctness-hardening/tasks.md → .kiro/specs/archive/billing-post-usage-correctness-hardening/tasks.md

@@ -191,3 +191,10 @@
 ## Completion Gate
 
 Do not mark this spec completed unless all P0 defects from the post-merge review have dedicated regression tests and the resulting implementation is the baseline used by `billing-architecture-final-convergence`.
+
+## Completion Status
+
+- [x] All Phase 0–5 implementation tasks completed.
+- [x] All post-merge review P0 defects have dedicated regression coverage.
+- [x] Certified implementation merged in PR #354 at `cd3a603495660f49240dcb9bf1698aa3f27503a2`.
+- [x] Successor baseline recorded; TUR/LUR cleanup remains successor scope.

.kiro/specs/billing-post-usage-correctness-hardening/validation.md → .kiro/specs/archive/billing-post-usage-correctness-hardening/validation.md

@@ -1,12 +1,12 @@
 # Validation and Successor Baseline
 
 Concise Phase 5 certification evidence for `billing-post-usage-correctness-hardening`.
-`spec.json` intentionally remains in `tasks-generated` with approvals and `ready_for_implementation: true`; it is not archived because the successor spec owns TUR/LUR cleanup.
+This spec is complete and archived after PR #354 merged. The successor spec owns only the explicitly deferred TUR/LUR cleanup.
 
 ## Baseline for `billing-architecture-final-convergence`
 
-- Main branch commit: `bdf6e5037c75a2586015cbf1ecac5207dadc3afe` (parent of this branch).
-- Working branch: `feat/billing-post-usage-correctness-hardening` (certification tree at commit `cdbb5d3f`).
+- Main branch commit: `cd3a603495660f49240dcb9bf1698aa3f27503a2` (PR #354 merge commit).
+- Certification head: `33d4c9042685d294933115f0bd9bd9e2e059d0c3` on `feat/billing-post-usage-correctness-hardening`.
 - Production shape the successor must preserve:
   - one `BillingCallID` per invocation; cheap credit screen -> route/quote -> atomic operational exposure admission -> billing-blind execution -> terminal leg/call records -> post-usage customer settlement (independent of provider-cost readiness).
   - positive persisted `attempt_seq` (v2 fingerprint) is the only legal customer-leg ordering source; `ExpectedBLegIDs` is a completeness set.