[Misc] Add repository agent notes

AGENTS.md

@@ -0,0 +1,43 @@
+# Repository Notes
+
+## Local Development
+
+- Use the Node version in `.nvmrc` (`v20`) when possible.
+- Install dependencies with `npm i`.
+- The README development flow is:
+
+```bash
+npm i
+npm run build
+npm run dev
+```
+
+- `npm run dev` runs `npm run rss` first, then starts Next.js on `http://localhost:3000`.
+- `npm run build` also regenerates `public/rss.xml` before building.
+- `npm run deploy` builds, exports, optimizes images for static export, and touches `out/.nojekyll`.
+
+## Content Layout
+
+- Blog posts live in `blog/*.md`.
+- A new blog post is picked up automatically by `src/pages/blog/[slug].js`; the URL slug is the markdown filename without `.md`.
+- Blog post frontmatter should include `title`, `author`, `date`, and `previewImg`.
+- Keep the first four frontmatter fields in this order when practical: `title`, `author`, `date`, `previewImg`. `scripts/gen-rss.mjs` parses those first four header lines directly for the RSS feed.
+- Newer blog index pages also read a `type` frontmatter field for the card label and category filters. Use `type: blog` for ordinary blog posts and `type: news` only for news announcements.
+- Non-blog content is mostly under `content/`, for example about, FAQ, impressum, team, and Vicuna evaluation content.
+
+## Images and Media
+
+- Put site images under `public/images`.
+- Put blog-specific images under `public/images/blog/<post-slug>/`.
+- Reference public assets from markdown and JSX with root-relative paths, for example `/images/blog/routellm/cover.png`, not `public/images/...`.
+- Blog card preview images use `frontmatter.previewImg` through `next-image-export-optimizer` in `src/pages/blog/index.js`.
+- Blog article pages render markdown with `markdown-it` and `html: true`, so existing posts often use raw HTML such as `<img src="/images/blog/...">` for sizing and centering.
+- Markdown image syntax also works in posts, for example `![caption](/images/blog/<post-slug>/figure.png)`.
+- MathJax is loaded from `src/pages/_document.js` using `public/mathjax.js` plus the CDN script.
+
+## Build Notes
+
+- A successful build currently emits warnings for outdated Browserslist data.
+- On Node 22, the build and dev server work, but Node prints `DEP0040` `punycode` deprecation warnings. Prefer Node 20 from `.nvmrc` for less noise.
+- Static generation currently warns that highlight.js cannot find the `bibtex` language for posts using BibTeX code fences.
+- Existing homepage lint warnings include a missing `useEffect` dependency in `src/pages/index.js` and an `<img>` without Next Image/alt handling.