These are all transitive dependencies (or unused) so they get pulled in
anyway.

In newer versions there is now a normal method for this which also supports
dynamically added components.

The static version is deprecated and removed in 2.0, so we need to port here.

Include the highlight.js css in all activities and move the
code css into the app, so it's defined where it is used.

It's confusing that there are two lock files in this repo and two
overlapping workspaces. Ideally everything should be in sync.

This has proper support for rollup while providing the same API.

This is what open-wc recommends now and uses in their @open-wc/testing package