Make UI more user friendly

[tegridyfarmer]

Moving the top bar to the bottom allows users to more easily tap the text and three dots.
The three for the settings would also be easier to reach, maybe a gear icon on the bottom is more fitting.

[felixwiemuth]

Sure, the whole reminders list screen is worth overhauling (at best implemented in Jetpack Compose), but currently the priority is on features, also as the reminders list is probably not used that often by most users.