Feature: Dedicated buttons for actions in the app

### Description

We have to use the on-screen buttons so as to dismiss or snooze the alarms as of now.

I propose a new feature :
- A feature (a tile) in the app settings, (tentatively) named as: `Physical buttons` that would define how to react to the pressing of the volume/power buttons when the alarm is ringing.
- The users can use them to
- Not do anything
- Snooze
- Dismiss

Users can easily snooze or stop an alarm without much hassle. This is particularly helpful in situations where the user may be in a meeting, and want a quick way to stop the alarm