add pause/resume API for remote control via iOS Shortcuts
POST /api/control/pause and /api/control/resume toggle notification
processing. when paused, the poller keeps running but skips processing
and doesn't mark notifications as read — they accumulate and get
processed on resume. authenticated via CONTROL_TOKEN bearer token.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>