Make Admin Navigation a dropdown on mobile

[christianhelp]

On a mobile view of the admin tabs, it is hard to see them and as we add more things, it would not hurt to make these easier to access. Ideally on mobile, compress all of the admin tabs into a dropdown in the top right corner.

[linear]

HK-200 Make Admin Navigation a dropdown on mobile

[joshuasilva414]

@jacobellerbrock Noticing some weird behavior on the admin side for mobile.

Looks good here. Although I would maybe suggest hiding the original navigation tabs on mobile?

The main issue is here:

When I switch to a view like "Users" where the content is wider than the screen, the navbar also becomes wider than the screen. Likely just need to set the navbar width to always be viewport width instead 100% container width