[codex-analytics] feature plumbing and emittance (#16640)

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[//]: # (BEGIN SAPLING FOOTER)
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* #16870
* #16706
* #16641
* __->__ #16640

codex-rs/app-server/tests/common/config.rs

@@ -78,3 +78,31 @@ model_provider = "{model_provider_id}"
         ),
     )
 }
+
+pub fn write_mock_responses_config_toml_with_chatgpt_base_url(
+    codex_home: &Path,
+    server_uri: &str,
+    chatgpt_base_url: &str,
+) -> std::io::Result<()> {
+    let config_toml = codex_home.join("config.toml");
+    std::fs::write(
+        config_toml,
+        format!(
+            r#"
+model = "mock-model"
+approval_policy = "never"
+sandbox_mode = "read-only"
+chatgpt_base_url = "{chatgpt_base_url}"
+
+model_provider = "mock_provider"
+
+[model_providers.mock_provider]
+name = "Mock provider for test"
+base_url = "{server_uri}/v1"
+wire_api = "responses"
+request_max_retries = 0
+stream_max_retries = 0
+"#
+        ),
+    )
+}