Document Windows exec-server test quirk

Author: adrian-openai

codex-rs/exec-server/src/server/handler/tests.rs

@@ -275,6 +275,7 @@ async fn output_and_exit_are_retained_after_notification_receiver_closes() {
             process_id.as_str(),
             shell_argv(
                 "sleep 0.05; printf 'first\\n'; sleep 0.05; printf 'second\\n'",
+                // `cmd.exe` retains the space before `&&` in `echo first && ...`.
                 "(echo first) && ping -n 2 127.0.0.1 >NUL && (echo second)",
             ),
         ))