The call wave sync watcher fired before DOM was updated (flush: 'pre'),
so ref callbacks hadn't registered host elements yet. Changed to
flush: 'post' so WaveSurfer instances are created after DOM refs exist.
Also fixed getCallItem to read from clientTimelineItems (source of truth)
instead of visibleThreadItems which could be stale.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
9b6e8291fe