Fix races in remote environment and session replacement tests (#52591)

## Why

The remote environment test can steer before the wait tool call is recorded, discarding the call. The session replacement test can close the client while agents overview RPCs are still pending, leaving the proxy writing to a closed socket.

## What changed

- Wait for the `wait-for-active-environment` function call event before steering the active turn.
- Wait for `AgentsOverviewThreadsLoaded` before shutting down session replacement test cases that open the agents overview.

GitOrigin-RevId: 886112a56ff6e1016efe30dbbd0256807bc1cc85

codex-rs/core/tests/suite/remote_env.rs

@@ -61,6 +61,7 @@ use codex_protocol::models::ActivePermissionProfile;
 use codex_protocol::models::FileSystemPermissions;
 use codex_protocol::models::PermissionProfile;
 use codex_protocol::models::PermissionProfileSnapshot;
+use codex_protocol::models::ResponseItem;
 use codex_protocol::models::SandboxPermissions;
 use codex_protocol::permissions::FileSystemAccessMode;
 use codex_protocol::permissions::FileSystemPath;
@@ -2438,7 +2439,14 @@ async fn future_pending_environment_can_finish_without_retargeting_the_active_tu
         }])
     };
     thread.start_or_steer_turn(request("wait")).await?;
-    wait_for_response_request_count(&response_mock, /*expected_count*/ 1).await;
+    // The HTTP request can arrive before its tool call is recorded. Steering
+    // at that point can preempt the response and discard the wait call.
+    wait_for_event(&thread, |event| {
+        matches!(event, EventMsg::RawResponseItem(raw)
+            if matches!(&raw.item, ResponseItem::FunctionCall { call_id, .. }
+                if call_id == "wait-for-active-environment"))
+    })
+    .await;
     assert!(matches!(
         thread
             .start_or_steer_turn(

codex-rs/tui/src/app/tests/new_session_tests.rs

@@ -152,7 +152,7 @@ async fn replacement_uses_server_defaults_and_preserves_explicit_launch_settings
             "medium",
         ),
     ] {
-        let (mut app, _events, _ops) = make_test_app_with_channels().await;
+        let (mut app, mut events, _ops) = make_test_app_with_channels().await;
         let server_home = tempdir()?;
         let client_home = tempdir()?;
         std::fs::write(
@@ -308,6 +308,16 @@ async fn replacement_uses_server_defaults_and_preserves_explicit_launch_settings
               server-model high · <PROJECT>
             ");
         }
+        if explicit.starts_with("profile_summary") {
+            // Opening the overview starts background RPCs. Let them finish before
+            // closing the client so the proxy is not writing to a closed socket.
+            loop {
+                let event = events.recv().await.expect("agents overview refresh");
+                if matches!(event, AppEvent::AgentsOverviewThreadsLoaded { .. }) {
+                    break;
+                }
+            }
+        }
         server.shutdown().await?;
         proxy.await??;
     }