Add turn_id to Codex skill invocation analytics (#21122)

codex-rs/analytics/src/analytics_client_tests.rs

@@ -1837,6 +1837,7 @@ async fn reducer_ingests_skill_invoked_fact() {
                 "plugin_id": null,
                 "repo_url": null,
                 "thread_id": "thread-1",
+                "turn_id": "turn-1",
                 "invoke_type": "explicit",
                 "model_slug": "gpt-5"
             }