This doesn't really add any tests, and we'll require many more additions
if we actually want to have full unit testing, but this at least makes
the tests pass when running `npm test`.
If we don't explicitly handle random unexpected exceptions, the error
that the front end receives includes a big ole stacktrace, which is
unhelpful for regular users and possibly bad to expose. Instead, we
should provide a vague "something went wrong" message.
Separately, we can create a default SnackBar options and use that (we
want it longer than 1.5 seconds because that's pretty short).
