Replace the combined "Round N — Name" string with a three-zone flex layout:
left (prev button + R{n} pill badge), center (prominent combatant name with
truncation), right (action buttons + next button). Adds 13 unit tests
covering all user stories including layout robustness and empty state.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
