v0.12.10: the newsroom publishes, and the first article written here

Articles are now written in this repository, in admin/content/articles/ (the article, its graph, its figures), and published by admin/build/publish.py. sgit.ai's generator has not moved yet, so the script borrows it without touching sgit.ai: it clones a read-only checkout into a temporary directory, replays this repository's history of the article sources into it (so each article's first-publish time and its versions stay true), runs the build, the cards, the banners and sgit.ai's validator there, and imports the result with sync_newsroom.py. Articles written here name this site's release in their byline. A slug or a figure that already exists on sgit.ai stops the run. This is the first step of the cutover, not the port of the generator.

The first article written and published here: Stop the bleeding, then ask for it back, a helper, an agent and a friendly letter for the subscriptions you keep and do not use.