008: Engineering as files: issues, releases, and the pages that render them

What is asked

The owner: a dev section where everything said in feedback is reverse-engineered into user stories and bugs, with mock-ups, Gherkin and screenshots when done; releases that list their issues; and the tracking as issues-fs, files in the repository, so every change to the site is connected to an issue and a version row can say which ids it answers.

Scenario

Given a card in admin/engineering/issues/open/
When the site is built
Then /engineering/ lists it under Open with its id, kind, priority and release
And /engineering/issues/NNN.html renders its body, Gherkin and all
When the card is moved to done/ with an Outcome appended
Then it is listed under Done, and the release page that names it links to it
And the version row names the ids

Outcome

Shipped in v0.12.1: admin/engineering/ (the files, in the Issues-FS-lite layout: open, blocked, done; releases), admin/build/engineering.py and md.py (the renderer), /engineering/ (the board, one page per issue, one per release, issues.json as a derived index), a link in the About menu. The sgit.ai board's own convention is the model; the full issues-fs CLI is not installable here, so the lite protocol is used as written.