Give every WordPress sub-category a home without a nav link

[ssavutu]

What

Freezes the subsection strip as it looks today, then files the WordPress sub-categories the import left behind as hidden subsections: a slug, a page and a place in the tree, but no link in the strip. Editors get full control of the row, including visibility and section ↔ subsection conversion.

Why

The taxonomy had two ways to hold a category and neither fit these. A subsection row gave a category a page and a nav link; an alias gave it neither, only a way to reach its section's page. So a category either joined the navigation or stayed anonymous — and 48 stayed anonymous, including 13 that matched nothing at all:

category	published articles	appeared on
wrestling	103	nothing
triangle talks	73	nothing
theater	28	nothing
sadie says, tech tuesday, wine reviews, administration, sjn grant, …	~90 combined	nothing

The other ~35 (tennis, crew, men's lacrosse, style, tv, beer reviews, editorial, letters to the editor, podcasts, word search, …) reached a section only through a category_aliases entry, so the category itself had no identity or page.

How

• site_taxonomy.is_visible, added by a runtime ALTER, defaulting to 1. That's the freeze: all 44 existing subsections keep their links unchanged, and everything seeded arrives hidden.
• Only subsectionsForSection filters on it. sectionMatchSlugs, taxonomyMatchSlugs and parentSectionForSubsection are untouched, so a hidden subsection's articles still roll up to its section, its own /v1/subsections/<slug>/articles still answers, and its counts still work.
• The seed runs once, flagged in cms_settings, because these rows are editable and a deploy must not undo an editor's deletion. It skips a slug already taken, and defers entirely against an empty taxonomy rather than burning its one run before the sections are imported. Each row carries its exact category title as an alias rather than trusting the slug to derive it.
• PUT /v1/taxonomy/{type}/{slug} now accepts type and is_visible, both omit-safe so a client that doesn't send them changes nothing. Conversion refuses to demote a section that still has children, and answers a (kind, slug) collision with a 400 instead of a driver-level 500. The slug guard is unchanged — renaming a slug that articles use still breaks live URLs.
• Sections screen: a Linked/Hidden column with a one-click toggle (which omits category_aliases, so it can't wipe matching rules), a show/hide filter, a Type select in edit mode with a URL-breakage warning, and a visibility checkbox in the editor.

Testing

go build; full go test including the DB-backed integration suites against a real MariaDB 11.8, with new tests for the seed's run-once / hidden / skip-taken properties, the visibility round-trip, and conversion in both directions; tsc; eslint; npm run build; swagger regenerated; Playwright screenshots of the sections screen and its editor.

Note for whoever deploys this

On the first boot the seed runs and recounts the rows it created, so the counts on the sections screen jump for Sports, Entertainment, Opinion, Columns and News. That's the previously stranded articles arriving, not a bug.

🤖 Generated with Claude Code