Add Page type and use Basic Page for all content

This only affects the Gallery Page right now, as this is the only additional content type. This gives us a strategy for all new content on the site. The Basic Page is just a single Layout Paragraph field allowing complete control over all elements on the page. If all additional components are added as paragraphs, then this is the only Content type we need.

How can we make View of certain types of content? Add a "Page Type" field.