separate chunks: sent ["hi"]; composer ""; status "prompt: admitted"
  order: interrupt start -> interrupt end -> takeover start -> takeover end -> prompt hi
one chunk after Ctrl-G: sent ["hi"]; composer ""; status "prompt: admitted"
  order: interrupt start -> interrupt end -> takeover start -> takeover end -> prompt hi
control: no earlier action: sent ["hi"]; composer ""; status "prompt: admitted"
  order: takeover start -> takeover end -> prompt hi
