Add new metrics to site admin usage statistics
Created by: lguychard
Implements the changes to /site-admin/usage-statistics
requested in #11063
Stacked on #11850, does not include relevant backend changes (cc @tsenart). I developed this against stub data in Storybook.
I want to call out a few liberties I took with the specified design @rrhyne @ebrodymoore:
- I re-used the tab component that's used in other parts of the app (repo rev sidebar, survey responses page, def/ref panels, campaigns...), which differs from the one in the Figma design.
- I used the
<ChartViewContent/>
component we use for code insights, which doesn't exactly match the charts from the Figma design. - "Download the usage stats archive" is included at the bottom of every tab because it seemed to make sense (versus only having it on the "features" tab).
For the first two points, this was out of convenience/speed -- we could tweak this to match the design 1:1, but it'll have to be done by someone else as I'll be