v0.12.113: @newsroom.dev: the page for publishers, kept current and versioned

For publishers, rewritten and now this site's own. The page for publishers was written once on sgit.ai on 11 October and imported here unchanged; a week of what matters most to a publisher was missing from it. Version 2.0.0 says what changed since: the meter charges for what is read, not what is scrolled; what was read folds away on a return visit; reviews on the record; the reader's vault on every device; search and ask; who is speaking; the publishers' section; the briefs. And it no longer depends on anyone remembering: What is live today is drawn from the features register, the newest for publishers from the publishers' section, and the five to start with from that section's own file, in every release.

• admin/content/publishers/page.md: the editor's text, with slots the build fills.
• admin/build/publishers.py: builds the page and its markdown twin; runs after sections.py.
• sync_newsroom.py: publishers/ is out of the import; a link to it from an imported page stays local.

A version history for one page. admin/build/page_versions.py, for any page this site writes: admin/content/publishers/versions.json lists the versions of the text with the hash of the source each was built from, and the build stops if the text changes without a new version; each version is frozen as markdown at publishers/versions/<version>.md by the release that made it; publishers/changes.json records, per release, what the live parts did. Versions of the page for publishers shows the versions, the differences between them block by block and word by word, and the ledger. v1.0.0 is the 11 October text, frozen from the imported twin.

The features register gains five entries a publisher can use: Ask the site (v0.12.9), Who is speaking (v0.12.85), Sections by audience (v0.12.108), The briefs, in the open (v0.12.109), and A version history for a page (this release).

Card 085.