feat: minor improvements to scheduled tasks

[ntorga]

1. ScheduledTasks is updated every 20s right now. When it does, the task that was expanded, collapses. We need to hold the state of which task is expanded on the $store so that when the footer is updated, the task does not collapse;
2. The command part of the ScheduledTasks could be converted into a textArea and have a copy to clipboard button. This is helpful when you want to re-run the command manually on the terminal. We could also have a textArea component that is read-only and won't show the X icon to clear the input field;
3. I'm missing a clear scheduled tasks button in the popover, it would help eliminate noisy, specially the failed tasks;
4. It would be great to have a button "Run Now" so we don't need to wait the 90s between executions;
5. We could have pagination for ScheduledTasks modal;