it should probably just do what the "topics" button does right now?

and the "topics" button should say something like "currently not yet implemented"?
or maybe we should just get rid of the "topics" button altogether for now

Context Behind this Problem

When the menu bar was first created, we envisioned having both a class and topic tree. When Max was writing the JS for the tree , he actually intended it to work for both. But it only really works as a class tree right now.
So the topic button loads the class tree right now and the classes button points to nothing, even though it should point to the same tree. @studycloud/back-end needs to get the /classes route set up to load a view of tree.blade.php.