fix(ci): classify repository skills coverage

tools/coverage/coverage-policy.json

@@ -277,6 +277,12 @@
                 "validationCommand": "pnpm nx test release-tools",
                 "reason": "Node tests validate release-note parsing, rendering and gate policy; the scripts are release tooling, not shipped source."
             },
+            {
+                "name": "repository-skills",
+                "root": "tools/skills",
+                "validationCommand": "pnpm nx test repository-skills",
+                "reason": "Node tests validate committed repository-skill metadata and documented paths; the validator is agent tooling, not shipped source."
+            },
             {
                 "name": "eslint-tools",
                 "root": "tools/eslint",