[iOS] Add support for iOS focus modes

[felix-bohlin]

Is there an existing issue for this?

• I have searched the existing issues

Proposed feature request

On iOS you're able to apply focus modes and filter out notifications from any app of your choosing. Pebble does however still show all incoming notifications regardless of focus mode.

Since iOS focus modes launched not long ago there's hopefully some extra metadata available that Pebble isn't currently using.

[jmhmd]

Would love to have this. Major use case for me is sleep focus, where most notifications are muted. As it stands my watch keeps buzzing in the middle of the night in my drawer.