Change navigation headers

[emmaleengo]

Migrate headers to cleaner headers that allow the user to see time/wifi-connection/battery. This also has a clean back arrow.

See example below:

See documentation here on some implementation of a navbar with back buttons:
https://developer.apple.com/documentation/uikit/uinavigationcontroller/customizing_your_app_s_navigation_bar

[Gerzer]

I think that we should hold off on implementing these design changes for now. We can discuss them perhaps this fall, and I’ll leave this issue open in the meantime.