feat: OSCBR optional provider, re-baseline after inactivity, field audit, provider UI/feature matrix tests, benchmark chain; 1.3.1

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

release/RELEASE_MANIFEST.json

@@ -1,14 +1,14 @@
 {
  "artifact": "RELEASE_MANIFEST",
- "GTI_FISCAL_VERSION": "1.3.0",
+ "GTI_FISCAL_VERSION": "1.3.1",
  "generated_at": "2026-09-25T15:43:40+00:00",
  "hub": {
-  "version": "1.3.0",
+  "version": "1.3.1",
   "api_compat": "1.0",
   "engine_version": "0.3.0",
   "decision_version": "mission-04c-ipi-ex-split"
  },
- "agent_version": "1.3.0",
+ "agent_version": "1.3.1",
  "fiscal_engine": {
   "ENGINE_VERSION": "0.3.0",
   "DECISION_VERSION": "mission-04c-ipi-ex-split",

release/VERSION

@@ -1 +1 @@
-1.3.0
+1.3.1