[FR] Add pop-up reminder type

[Nitero]

I'd love to get a new type of reminder that works like the pop-ups in TickTick.

Basically I want a middle ground between push notifications (easy to ignore) and alarm notifications (in-your-face). Ideally it would show up over other apps like in TickTick, or alternatively just full screen. The main thing is that it should stay until you decide what to do with it (complete/snooze). This way it isn't too distracting because it makes no sounds, but I also don't completely miss it because I didn't see the push notification.

PS: Am considering switching over from TickTick. I love the app so far, thanks for making it!