v0.9.5

Added

• Share images. An image key in a post's front matter, or in blogin.json as
  the default for every other page, makes head-meta write og:image as an
  absolute URL under base-url, pointing at the fingerprinted name when
  fingerprint is on. og:image:width and og:image:height are read from the
  file's PNG, JPEG, GIF, or WebP header, and twitter:card becomes
  summary_large_image. The build warns about an image it cannot find or
  measure.
• On post pages, head-meta writes article:published_time from date,
  article:modified_time from a new updated front-matter key, and one
  article:tag per tag.
• JSON-LD structured data: a BlogPosting on each post page and a WebSite on
  the front page.
• The sitemap gives each post a <lastmod>, from updated or else date.
• head-meta links each configured site-wide feed with <link rel="alternate">.
• noindex: the 404 page, listing pages after the first, and any post with
  noindex: true carry a robots noindex tag and are left out of the sitemap.
• A twitter key in blogin.json, written as twitter:site and
  twitter:creator.

Fixed

• A long run of operators in a template expression, such as 1 + 1 + 1 ...
  thousands of terms long, overflowed the stack while it was evaluated. A chain
  is now measured as it is parsed and refused past the same 64-level limit that
  parentheses already had, with a "nested too deeply" error.
• A section's layout in blogin.json was read and then ignored, so its posts
  rendered through show.haml. They now render through the named layout, after
  a post's own front-matter layout and before show.haml.
• The scaffolded show.haml wrote the date line as an expression string, which
  does not interpolate, so every post on a new site showed
  #{date} · #{reading-time} min read. It is HAML text now and shows the date
  and reading time.
• Rendering threads now get an 8 MiB stack on every platform. macOS gives a
  new thread 512 KiB, which an expression nested to the evaluator's limit could
  overflow in a sanitizer build.

Testing

• scripts/test.sh runs one stage at a time and stops at the first stage that
  fails. That stage's output is printed and kept in build/test-logs/, along
  with every other stage's. --serial is gone, and -j sets the cores each
  stage gets.
• A stage now stops at its first failing command. Before, bash ignored set -e
  inside the stage, so a failed build went on to run the specs against the
  previous binary.

Dependencies

• The Debian base image of the build container moves from 34cd9e9 to
  f324c7f.
• The container build retries the apt.llvm.org key fetch for four minutes
  instead of about 50 seconds.
• codecov/codecov-action moves to 7.1.1, and the CodeQL actions to 4.38.0.