Follow only this viewer's answers and keep the Document cue still

- Follow a resumed turn only after this viewer's own answer, and forget it if
  no turn starts within 3s, so discards, other people's answers and unrelated
  turns never read as the Planner writing.
- Run the pulse only under prefers-reduced-motion: no-preference.
- Show writing as a ring and waiting changes as a filled dot.
- Place the desktop dot in the button corner so the Decisions pill never moves.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>