Doc pages get their descriptions back

A documentation page carries its one-line summary in YAML front matter. That summary is what you read on a catalog card, in a table of contents, and in search results.

Thirty-three pages had none, and the page itself looked perfectly fine.

Two different ways to lose a line of text

Twenty pages had front matter a YAML parser refuses outright — almost always a value containing ": ", which YAML reads as the start of a nested mapping:

Description: … and the shape most of these share: a narrow instrument answering correctly

The import does not fail. It falls back to a rescue that recovers the name, category, icon, state and order — and not the description. So the page lands, renders and is findable by title, with an empty summary everywhere a summary is shown.

Thirteen more parsed perfectly and were simply cut short. An unquoted # opens a YAML comment, so a description ending in an issue reference lost everything from the # onward:

Description: … and the repair path both decisions had to leave open — issue #2993.
#                                                                      ↑ everything from here was dropped

Both halves are fixed. Long values are now folded block scalars, which need no escaping and read better at this length.

Why it went unnoticed for weeks

The test watching What's New entries checked that each one carries a Description: — by matching the text with a regular expression, the same way the rescue does. A line the regex finds and the parser refuses satisfied it. Twelve entries were green in that test and description-less in the mesh at the same time.

A new guard runs the real YAML parser across every front-matter block in the documentation tree, and a second one catches the truncating #. Both are the checks that already existed for the repository's skill files, pointed at the tree that was missing them.