Overview

Enable users to mark a "split" in their post, where all content beforehand is available to all readers (subject to blog / "collection" permissions) and all content after the split is unlocked only if the reader is using Web Monetization.

Implementation

1. Create a new shortcode: <!--premium--> <!--paid--> that indicates where content is split
2. When rendering a collection or post, hide all content after the split
3. Rely on client-side JS + an Unlocking API to return everything else.

TODO: implementation details for item #3.