Feat: Students CRUD

[sean-dickinson]

What

• Adds Student CRUD screens
• Removes useless local CI step for testing seeds (I don't run seeds in the test environment)

Why

• Clearly there are already opportunities for drying things up regarding the forms, breadcrumbs, styling etc. For now I'm leaving everything as copy/paste until there's a clear enough pattern that's worth abstracting.
• Note that I chose keeping the students resource shallow nested rather than fully nested as I think this is a better call for the long term as otherwise it can get awkward to use the route helpers.