test(cli): map /api/client-config to ocx export in the parity sweep

The headless-parity sweep asserts every GUI management endpoint has a
documented CLI resource. Phase 030 added GET /api/client-config without
registering it, so the sweep went red — correctly: the route and the CLI
command shipped in the same unit and `ocx export` is exactly its mirror.

Author: lidge-jun

tests/cli-headless-parity.test.ts

@@ -71,6 +71,7 @@ describe("headless GUI parity CLI", () => {
       ["/api/custom-models", "ocx models"],
       ["/api/model", "ocx models"],
       ["/api/combos", "ocx combo"],
+      ["/api/client-config", "ocx export"],
       ["/api/debug", "ocx debug/observe"],
       ["/api/diagnostics", "ocx system"],
       ["/api/effort", "ocx agent"],