How do I add a page to /tag/ using Publii?

Perfect! That’s what’s missing.

But it’s really important to make that page manageable:

1. I definitely want a list of all used tags – a pretty tag cloud would be perfect but a simple list sufficent.
2. But I really want to add text to this page as well. It should be editable just like any other post, followed by the list/cloud of tags.

Thank you!