Routing: Dashboard pages do (some) routing manually

[Danziger]

ArConnect/src/routes/dashboard/index.tsx still performs routing manually in the center panel. That should be replace with <Routes>, just like it's been done for the third panel in #556.

This change should also allow the removal all usages of wouter's useRoute() in Dashboard views. The params should instead come from the view props (props.params). That requires some views to be refactored to use the router <Routes>.