Re-order Sidebar

[twblack88]

So we don't lose the thread/idea.

We currently have sub-headers that aren't being used:

• [ ] wallet has my wallet underneath. We should just keep the route to mywallet

explore will stay and we'll nest underneath:

• [x] assets
• [ ] markets #7477
• [ ] FOX page (previously FOX benefits) #7834

For each explore route, it should also get a card on mobile. This puts discovery at the bottom and activity at the top.