pub async fn pause(
app: AppHandle,
scheduler: State<'_, Scheduler>,
duration_secs: Option<u64>,
) -> Result<(), String>Expand description
Pause the scheduler. duration_secs = None pauses indefinitely;
Some(n) pauses for n seconds. Fires pause_start hooks and
emits the pause:changed event. Idempotent — a pause-while-paused
updates the deadline but doesn’t re-fire hooks.