Allow using volume keys for user-selectable actions

[LucaMkIII]

Checklist

• [X] I made sure that there are no existing issues - open or closed - to which I could contribute my information.
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• [X] I have taken the time to fill in all the required details. I understand that the bug report will be dismissed otherwise.
• [X] This issue contains only one feature request.
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Feature description

Allow customization of how the volume buttons behave while an alarm is going off.

For example, they could be set to

• Snooze alarm
• Stop alarm
• Silence (but do not stop) alarm
• Stop vibration (but not sound) of the alarm
• Adjust alarm volume (Not just system/media volume, though I don't know how many devices support independent alarm volume control)
• Do nothing (prevent the phone from doing something if I accidentally bump the volume buttons)
• Don't override volume behavior (Retain current behavior. For me, this is to adjust media volume.)

Why do you want this feature?

This is based on a feature found in other clock apps.

My personal use case: I sometimes like to adjust my alarm volume without stopping my alarm, which allows me to keep being notified while not disturbing the (still sleeping) people I live with. This feature would make it easier for me. But some people prefer the volume buttons to stop or snooze the alarm. So it shouldn't just be a permanent change for everyone.

Additional information

I've only seen some of these behaviors available in other clock apps. I would be happy with just a subset of these options, but I can imagine use cases for each of the options listed.

[StorageB]

Agreed that this would be an excellent feature to have.

The screenshot below shows how it was implemented in the default clock app on my previous phone. There was an option to set the volume and power buttons to snooze, dismiss, or do nothing.

The other features @LucaMkIII mentioned would be nice as well, but at a minimum I think snooze, dismiss, and do nothing would be a good set of basic options to have.