ActivityPub: Use Title, Excerpt & Link, rather than full article

[cerebrate]

There is a more detailed description of why this is useful and how it could be implemented in the reply here:

ActivityPub: Use title & excerpt, rather than full article

Okay, so I don’t actually speak TypeScript, but I took a look at the source code anyway, which seems to back up my hypothesis. The posts that get published to ActivityPub are created in Post.createArticleFromGhostPost here, and relevantly, include all the relevant data - title, excerpt, summary, content, URL, etc., per lines 459-477. Per line 464 in particular, it publishes these to ActivityPub as a post/payload of type Article. Turning to the Mastodon documentation on payloads here, we see th…