Revamp playground page #29
Description
Currently our playground page (which is under docs) is pretty standard with the examples dropdown, and window for code and result.
We can definitely do better, in terms of design, an inspiration could be from here: https://lit.dev/playground/
where they also have the code and result, but have the examples laid out in the sidebar, which is easier to navigate
plus we can take advantage of SEO here, since every example page will be its own page.
note on existing urls: we need to redirect them to the new one, if we ever decide to do it.