Organize top navigation bar

• The nav bar is currently broken at four different screen widths- the far right content is completely inaccessible.
• !17529 (merged) fixes this short-term by moving content into dropdowns at different screen widths

Long-term, we should re-think how many items are in our nav bar. Is it necessary to have them all there? Where else can they go?

I've reached out to @donaldcook to get data on which nav items are currently being tracked, and would like to start tracking the rest of them too.