Add 5s timeout to models list call + integration test (#8942)

- Enforce a 5s timeout around the remote models refresh to avoid hanging
/models calls.

codex-rs/core/src/models_manager/manager.rs

@@ -12,6 +12,7 @@ use std::sync::Arc;
 use std::time::Duration;
 use tokio::sync::RwLock;
 use tokio::sync::TryLockError;
+use tokio::time::timeout;
 use tracing::error;
 
 use super::cache;
@@ -21,6 +22,7 @@ use crate::api_bridge::map_api_error;
 use crate::auth::AuthManager;
 use crate::config::Config;
 use crate::default_client::build_reqwest_client;
+use crate::error::CodexErr;
 use crate::error::Result as CoreResult;
 use crate::features::Feature;
 use crate::model_provider_info::ModelProviderInfo;
@@ -29,6 +31,7 @@ use crate::models_manager::model_presets::builtin_model_presets;
 
 const MODEL_CACHE_FILE: &str = "models_cache.json";
 const DEFAULT_MODEL_CACHE_TTL: Duration = Duration::from_secs(300);
+const MODELS_REFRESH_TIMEOUT: Duration = Duration::from_secs(5);
 const OPENAI_DEFAULT_API_MODEL: &str = "gpt-5.1-codex-max";
 const OPENAI_DEFAULT_CHATGPT_MODEL: &str = "gpt-5.2-codex";
 const CODEX_AUTO_BALANCED_MODEL: &str = "codex-auto-balanced";
@@ -105,10 +108,13 @@ impl ModelsManager {
         let client = ModelsClient::new(transport, api_provider, api_auth);
 
         let client_version = format_client_version_to_whole();
-        let (models, etag) = client
-            .list_models(&client_version, HeaderMap::new())
-            .await
-            .map_err(map_api_error)?;
+        let (models, etag) = timeout(
+            MODELS_REFRESH_TIMEOUT,
+            client.list_models(&client_version, HeaderMap::new()),
+        )
+        .await
+        .map_err(|_| CodexErr::Timeout)?
+        .map_err(map_api_error)?;
 
         self.apply_remote_models(models.clone()).await;
         *self.etag.write().await = etag.clone();