feat(F-091): completed feature

work/artifacts/F-091/security.json

@@ -0,0 +1,13 @@
+{
+  "feature_id": "F-091",
+  "agent": "security",
+  "verdict": "APPROVED",
+  "summary": "The fix does not relax uniqueness or alter authorization. Conflict messages reveal only that the submitted SKU/EAN is already in use, without exposing another variant's identity or data.",
+  "evidence": [
+    "Database UNIQUE constraints remain authoritative for SKU and EAN",
+    "No SQL interpolation or new input path added",
+    "Only field type (SKU/EAN) is returned, not conflicting records",
+    "No dependencies, secrets, auth, or permission changes"
+  ],
+  "timestamp": "2026-08-20T19:47:10Z"
+}