Articles fold in a feed, with their cover, excerpt and a Read button

An Article or a Page with its title, or a titled post longer than a few paragraphs (WriteFreely sends its posts as Notes
with a name), shows its cover, its excerpt and a Read button in a feed, and its whole text on demand; the post opened
in its thread shows whole. A feed of Ghost, WordPress and WriteFreely long reads stays a feed. tests/e2e ArticleTests
checks it with a WriteFreely blog; the render matrix still passes (70).

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01LsXgEaXee4GCU1hwYgPJXw

CLAUDE.md

@@ -252,6 +252,9 @@ supplies:
   lists, notifications, public feeds, threads around the opened post, profiles; none for favourites, bookmarks,
   conversations and search), and the card leaves the post out (hide), folds it behind the filter's title (warn) or blurs
   its media (blur).
+- **Articles** fold in a feed (`Content.IsFoldedArticle`): an Article or a Page with its title, or a titled post longer
+  than a few paragraphs (WriteFreely sends Notes with a name), shows its cover, its excerpt and a Read button; the
+  post opened in its thread shows whole.
 - **The composer** (`Components/Composer.razor`) writes a post, a reply (`InReplyTo`), a quote (`Quoting`, offered on a
   card when the server says the persona may quote it) or an edit of the persona's own post (`Editing`: its words and
   warning from `/source`, a PUT that keeps its media, visibility and poll); a post can hold a poll instead of media.