Use current session settings for review threads (#36941)

## Why

Reviews may use a different model from their parent turn. They need current
thread settings without inheriting defaults resolved for the parent model.

## What changed

- Build review configuration from the parent turn context while preserving
  explicitly configured token-budget overrides.
- Use the review model's token-budget defaults and select a supported reasoning
  effort when switching models.
- Carry the session's resolved service tier and current environment,
  permissions, and approval settings into the review thread.

## Testing

Expanded review coverage for updated thread settings, model-specific
token-budget defaults, service tiers, and reasoning effort selection.

GitOrigin-RevId: cefa0f22cd9b9e28047d94e1d2d49ff83eded43e

codex-rs/core/src/session/mod.rs

@@ -636,6 +636,7 @@ impl Session {
         let model_info = models_manager
             .get_model_info(model.as_str(), &config.to_models_manager_config())
             .await;
+        let configured_config = Arc::clone(&config);
         if config.config_lock_export_dir.is_some()
             && config.config_lock_save_fields_resolved_from_model_catalog
         {
@@ -767,7 +768,7 @@ impl Session {
         // This task will run until Op::Shutdown is received.
         let session_for_loop = Arc::clone(&session);
         let session_loop_handle = tokio::spawn(async move {
-            submission_loop(session_for_loop, config, rx_sub)
+            submission_loop(session_for_loop, configured_config, rx_sub)
                 .instrument(info_span!("session_loop", thread_id = %thread_id))
                 .await;
         });