[erinxocon]

Description:
Site Audit flags tech-docs pages under "Article page missing Article schema". This adds schema.org
TechArticle structured data to the docs pages through a Starlight route middleware.

What changed

• New src/plugins/techarticle-json-ld-middleware.ts, registered in astro.config.ts (routeMiddleware
  is now an array: the existing ToC middleware plus this one).
• It pushes a <script type="application/ld+json"> into starlightRoute.head. No component overrides.
• Fields: headline (page title), description (only if the frontmatter has one), url and
  mainEntityOfPage (reuses Starlight's canonical link, so the /tech-docs base and host are right per
  environment), dateModified (git last-updated, omitted if unavailable), inLanguage, author,
  publisher.
• Skipped on 404, the landing page and /archive/, which aren't articles.
• < is escaped as \u003c so page text can't close the script tag.

[jacobgkau]

Seems very silly that a tool could already tell this was an article, we already provided all of the data it's asking for, but we need to copy the data from one set of tags into another to increase an audit score. But I don't see any problems with what's being added.

I still think canonical URLs without the trailing slash would've been better for articles, but again, we already list <link rel="canonical" href="... with the trailing slash, and what's being added here matches that.