Demonstrates the 'every input acts, may speak' pattern without bridging: a
standard voice pipeline (STT → LLM → TTS) whose LLM only converses, plus a
separate UIWorker that does all the list work. The voice pipeline's user
aggregator fires on_user_turn_stopped each turn and dispatches the transcript
to the UIWorker as a respond job (a bus message); the UIWorker reads the
auto-injected <ui_state> snapshot and drives the list silently via add_item /
set_checked / remove_item commands (plus the standard highlight). Items are
checkboxes whose label and checked state the snapshot exposes.
Includes a vanilla-JS client following the existing UI-demo client style.
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