test(breadcrumbs): cover missing representation route map fallback

memory-bank/change-log.md

@@ -860,6 +860,33 @@ Follow-ups:
 - Closure slice 2: add focused negative-path representation map/dependency tolerance test coverage.
 - Closure slice 3: resolve and guard remaining `/newappeal` inline edge branch treatment.
 
+### CL-22541-Z2: breadcrumbs closure slice 2 — missing representation map negative-path guard
+
+date: 2026-04-09  
+author: Cline  
+scope: `tests/phase22/breadcrumb-route-maps-helper.test.cjs`  
+type: change  
+rationale: Execute closure slice 2 by adding focused negative-path coverage ensuring resolver behavior remains stable when representation route-map dependency is missing from grouped map input.  
+impact: Test hardening only; no runtime route/auth/session/API/EN-CY/a11y behavior change.
+status: completed
+
+Summary:
+
+- Added focused helper-level test:
+    - `resolveMappedRouteRenderer tolerates missing representation map entry in grouped map input`
+- New assertions verify:
+    - missing `representationRouteRenderersByPath` resolves `/myportal/representation` to `null`
+    - later maps still resolve correctly (case detail fallback remains intact).
+
+Validation:
+
+- `node tests/phase22/breadcrumb-route-maps-helper.test.cjs` -> pass (7/7).
+- `node tests/phase22/index.test.cjs` -> pass (combined suite).
+
+Follow-ups:
+
+- Closure slice 3: resolve and guard remaining `/newappeal` inline edge branch treatment.
+
 ### CL-00X: 22500 `components/elements/index.js` Phase 1 helper extraction
 
 date: 2026-04-07