Update build process and enhance curriculum content: Add a new script for generating site metadata to improve SEO with automatic sitemap and feed generation. Modify the build command to include this new script, ensuring it runs before the Zola build. Update the math curriculum to reflect the status change of the "Linear inequalities in one unknown" chapter to live, and enhance the chapter content with detailed explanations and examples. Adjust contributor roles in the JSON data for clarity.

.agents/skills/ofb/SKILL.md

@@ -33,6 +33,7 @@ frontend/                  → catalog-app, Mermaid map view, site chrome
 ```bash
 bun install
 bun run build:js    # after frontend/ changes
+bun run generate:site-metadata  # regenerate static/sitemap.xml + static/feed.xml from content + git log
 bun run index:search  # once per dev session (copies public/pagefind → static/pagefind)
 zola serve          # http://127.0.0.1:1111
 bun run build       # production: JS + Zola + pagefind → public/
@@ -59,10 +60,20 @@ bun run build       # production: JS + Zola + pagefind → public/
 | New subject (sidebar) | `data/catalog.json` → `subjects[]`; `data/{id}-curriculum.json` (catalog template auto-loads by `id`) |
 | New chapter (planned) | `{subject}-curriculum.json` strand entry; optional `graph.edges` |
 | New chapter (live) | Above + `content/{subject}/{slug}/_index.md` + HTML partial + `chapter.html` wiring + `main.tsx` widget mount if interactive |
+| Sitemap/feed coverage | `scripts/generate-site-metadata.ts`, `static/sitemap.xml`, `static/feed.xml`, `package.json` build script |
 | Homepage subject card | `themes/.../templates/index.html` (not yet data-driven) |
 | Browse / nav URL | `zola.toml` `[extra] browse_url` + `base.html` site-config + `main.tsx` fallback |
 | Search UI / index | `base.html` (Pagefind assets + modal), `content/search.md`, `_search.scss`; `bun run index:search` for dev |
 
+## Sitemap / feed auto-generation
+
+- `bun run generate:site-metadata` generates:
+  - `static/sitemap.xml` (all user-facing built pages + live chapters)
+  - `static/feed.xml` (RSS 2.0 for pages + live chapters)
+- URL timestamps come from `git log -1` on content-source paths. If a page/chapter has no commit yet, generator falls back to filesystem mtime.
+- Build pipeline runs this automatically before `zola build` via `package.json`.
+- Include only resolvable pages; planned chapters without live content are excluded.
+
 ## Search (Pagefind)
 
 | Piece | Path |