v0.4.0 — filesystem-IA + engine console

[0.4.0] — 2026-10-17

The filesystem-IA + public-surface release: the content tree is now the
site's information architecture, and the packaged console became a real
engine-driven shell.

• Filesystem-IA (docs/decisions/2026-10-17-filesystem-ia.md): the content tree is the site structure — dirs → sections/headings, files → entries, root *.yaml lists → sections, dotfiles console-only. projectSiteTree() in @shellside/site; demo index + [dir]/[...id] consume it; .site/.meta hidden plaintext config readable via cat in console.

• /llms.txt surface behind surfaces.llmsTxt; surfaces.devDesk marked planned (LAB-1519).

• Packaged console: less overlay pager, clickable fs entries, open <file> follows node.url, console.helpTopics config.

• Default skin: dark-mode + focus-visible pass on demo/template css.

• @shellside/console-engine gained createHistory (ring + draft restore) and completeLine (lcp + cycle on repeat Tab); the packaged /console page is now a bundled engine-driven shell — pipes, grep/find/head/tail/wc/sort/uniq/diff/strings, ls/cd/cat/tree/open, ↑/↓ history, Tab completion — replacing the hand-rolled if/else shell.

• apps/demo — self-describing demo on GitHub Pages (shellsite instance; packages as entries, docs as writing, releases as records). .github/workflows/pages.yml builds packages → demo → leak-audit gate → deploy.