Content cleanup: drop news, new profiles, link-check fixes

.github/workflows/jekyll.yml

@@ -6,8 +6,8 @@ on:
   # Pull requests get a build check (no deploy) so broken changes are caught before merge
   pull_request:
     branches: ["main"]
-  # Daily rebuild: date-driven content (current semester, conference deadlines,
-  # expiring news) must move on even when nobody pushes
+  # Daily rebuild: date-driven content (current semester, conference deadlines)
+  # must move on even when nobody pushes
   schedule:
     - cron: "0 4 * * *" # 04:00 UTC = 07:00 Moscow
   workflow_dispatch:

.github/workflows/links.yml

@@ -24,12 +24,18 @@ jobs:
         with:
           # Only real http(s) URLs (skips Liquid paths like {{ site.baseurl }}/...).
           # Academic profile hosts block bots, so 403/429 are not failures.
+          # --root-dir resolves root-relative image paths (/images/...) in blog posts.
+          # NIR and thesis tables are an archive: dead student repos there are expected.
           args: >-
             --no-progress
             --scheme http --scheme https
             --accept 200..=206,403,429
             --timeout 20
             --max-concurrency 8
+            --root-dir ${{ github.workspace }}
+            --exclude-path '_i18n/en/nir.md'
+            --exclude-path '_i18n/en/thesis.md'
+            --exclude '%7B%7B'
             --exclude 'scholar\.google\.com'
             --exclude 'elibrary\.ru'
             --exclude 'scopus\.com'

AGENTS.md

@@ -0,0 +1,134 @@
+# Intelligent Systems Department Website — Agent Instructions
+
+Jekyll 4.3 static site for the Intelligent Systems Department (MIPT), deployed to GitHub Pages via GitHub Actions.
+Bilingual (EN default at `/`, RU at `/ru/`) using `jekyll-multiple-languages-plugin` 1.8.
+
+## Build & deploy
+
+- Local: `bundle install && bundle exec jekyll serve` (Ruby 3.1 in CI).
+  With macOS system Ruby use `BUNDLE_PATH=vendor/bundle bundle install && BUNDLE_PATH=vendor/bundle bundle exec jekyll build`.
+- Sass is compiled by `jekyll-sass-converter` 2.x (libsass) on purpose: no dart-sass binary and no `@import` deprecation noise.
+  libsass evaluates CSS `min()`/`max()` as Sass math — wrap them in `unquote("...")` (see `_sass/_toc.scss`).
+- Deploy: push to `main` triggers `.github/workflows/jekyll.yml` (optimize images → build → deploy to Pages).
+  Pull requests to `main` run the same build without deploying.
+  The site is also rebuilt **daily** (cron) so date-driven content — current semester, upcoming deadlines — follows the calendar without commits.
+- Automation workflows: `refresh-data.yml` (weekly data refresh + deploy), `links.yml` (weekly dead-link report → issue labelled `broken-links`).
+  No Dependabot on purpose — dependency bumps are done by hand when needed.
+  Optimized images are cached by the hash of the originals (`actions/cache`), so the slow step runs only when images change.
+- `.github/workflows/links.yml` checks all external links weekly (lychee); a red run means a dead link in content.
+- There is no other deploy path; `_site/`, `vendor/` and `Gemfile.lock` are gitignored.
+
+## Architecture: how i18n works (critical)
+
+Every content page exists in TWO places:
+
+1. A **stub** at the repo root (e.g. `nir.md`) or in a collection (`_people/*.md`, `_course/*.md`).
+   The stub holds ONLY front matter (title key, permalink, layout data) and a `{% tf <file>.md %}` tag.
+2. The **actual content** in `_i18n/en/<file>.md` and `_i18n/ru/<file>.md`.
+   `{% tf %}` pulls the file for the current language.
+
+Translation strings (nav names, page titles, people/course display names) live in `_i18n/en.yml` and `_i18n/ru.yml`.
+Templates use `{% t key.path %}` to resolve them.
+Missing RU content files fall back to EN (currently missing in `_i18n/ru/`: `conferences.md`, `nir.md`, `seminars.md`, `templates.md`, `thesis.md` — intentional, they render EN content).
+
+**Rule: never put visible text in a root stub — put it in `_i18n/{en,ru}/`.
+Never add a person/course without registering its display name in BOTH `en.yml` and `ru.yml`.**
+
+## Directory map
+
+| Path | Purpose |
+|---|---|
+| `_config.yml` | Site config, nav menu (`nav.pages`), collections, defaults, roles/types enums (`global.people.roles`, `global.course.types`), `logo` (large, for Open Graph) / `navbar_logo` (small) |
+| `*.md` (root) | Page stubs: front matter + `{% tf %}` only. Permalinks like `/materials/nir/` are set here |
+| `404.html` | Not-found page (bilingual, served by GitHub Pages for any missing URL) |
+| `_i18n/en.yml`, `_i18n/ru.yml` | ALL translation strings: nav, titles, `people:` names, `courses:` names |
+| `_i18n/{en,ru}/*.md` | Real page content per language |
+| `_i18n/{en,ru}/_people/*.md` | Person biographies (rendered under profile header) |
+| `_i18n/{en,ru}/_course/*.md` | Course descriptions |
+| `_people/*.md` | Person stubs: `position` (role), `avatar`, contact/scholar links. Filename = `lastname_ii.md` |
+| `_course/*.md` | Course stubs: `type` (bachelor/master/deprecated/draft), `lecturers` (comma-separated people IDs), `site` |
+| `_blogs/*.md` | Blog posts — full content directly here (NOT via `_i18n`), EN only. Filename = URL slug (`/materials/blog/<slug>/`) |
+| `redirects/*.md` | Front-matter-only stubs with `layout: redirect` that keep old URLs alive (`permalink:` old, `redirect:` new) |
+| `_data/schedule.yml` | THE schedule: semesters (dates, key dates in EN+RU, timetables). Rendered on `/education/` by `_includes/schedule.html` → `schedule_semester.html` → `schedule_table.html` / `date_list.html`; admission-tagged dates also on `/admission/` via `admission_dates.html` |
+| `_data/conferences.yml` | Conference deadlines for `/materials/conferences/`; entries with `ccfddl:` are auto-refreshed weekly from ccfddl/ccf-deadlines by `scripts/update_data.py` |
+| `_data/stats.yml` | Home page numbers (GitHub repo count), auto-refreshed weekly by `scripts/update_data.py` |
+| `scripts/update_data.py` | Data refresh script run by `.github/workflows/refresh-data.yml` (commits to `_data/`, then triggers a deploy) |
+| `_layouts/` | `default` (base HTML, all `<head>` assets), `page`, `profile`, `course`, `blog`, `redirect` |
+| `_includes/` | `navbar`, `footer`, `seo` (meta + JSON-LD), `edit` (floating edit button), `toc`, `blog-grid`, `schedule_table`, `person-card` (avatar+name card, pass `id=` or `profile=`), `social-links` (the department's social links, pass `link_class=`) |
+| `_data/profile_links.yml` | Ordered list of contact/academic link types on profile pages; add an entry here to support a new link field in `_people/*.md` |
+| `_sass/` + `style.scss` | Styles; `style.scss` imports all partials; variables in `_sass/_variables.scss`; `_fonts.scss` (self-hosted Open Sans `@font-face`), `_icons.scss` (SVG-mask icons replacing Font Awesome/academicons), `_bootstrap_shim.scss` (structural navbar rules copied from Bootstrap 3) |
+| `fonts/` | Self-hosted Open Sans woff2 (variable, latin+cyrillic; declared in `_sass/_fonts.scss`) |
+| `javascript/` | Vanilla JS, no jQuery/Bootstrap: `navbar.js` (collapse+dropdowns), `carousel.js` (scroll-snap carousel), `toc.js`, `fade_in.js`, `copy_email.js`, `table_scroll.js`, `mermaid_init.js`, `prevent_flash.js` |
+| `images/people/` | Avatars (filename referenced in `_people/*.md` `avatar:` field; `default.jpg` fallback) |
+| `images/blog/<post-slug>/` | Blog images, folder named after the `_blogs/*.md` filename |
+
+## Recipes
+
+### Add a person
+1. Create `_people/lastname_ii.md` (copy an existing one): set `title: people.lastname_ii`, `position:` (one of `hotd|dos|phd|pgs|gs`), `avatar:`, links.
+2. Create `_i18n/en/_people/lastname_ii.md` and `_i18n/ru/_people/lastname_ii.md` with the bio.
+3. Add `lastname_ii: Name Surname` under `people:` in `_i18n/en.yml` and the Russian name in `_i18n/ru.yml`.
+4. Add the photo to `images/people/` (any jpg/png as is — CI compresses it at deploy time).
+URL becomes `/people/lastname_ii/`.
+
+### Add a course
+1. Create `_course/course_name.md`: `title: courses.course_name`, `type:`, `lecturers:` (people IDs, comma-separated, no spaces), `site:`.
+2. Create `_i18n/{en,ru}/_course/course_name.md` with the description.
+3. Register `course_name:` under `courses:` in both `en.yml` and `ru.yml`.
+The course auto-appears on `/course/`, home page, lecturer profiles ("Teaches" section), and the schedule if referenced in `_data/schedule.yml`.
+
+### Add a blog post
+1. Copy an existing post (e.g. `_blogs/hyperband.md`) to `_blogs/<slug>.md` — a short descriptive slug, it becomes the URL; fill `title`, `date`, `authors`, `summary`, `tags`, `read_time`, `cover`.
+2. Put images in `images/blog/<slug>/` (as is — CI compresses at deploy time).
+3. Start body headings at `##` — the layout already renders the title as `<h1>`.
+URL becomes `/materials/blog/<slug>/`. Never rename a published post without adding a stub in `redirects/`.
+
+### Add a semester / update the schedule
+Everything is in `_data/schedule.yml` — never edit semester blocks in `education.md` (the pages only hold the intro links and `{% include schedule.html %}`).
+1. Append a semester: `id` (`fall_2026`), `season`, `year`, `start`/`end` (set `end` to the day before the next semester starts), `draft: true` while preliminary.
+2. `key_dates`: `{date, [date_end], en, ru, [tag: admission]}`; text is markdown, internal links as `({baseurl}/materials/...)`.
+3. `groups`: one per year of study — `{year_of_study, semester, day, courses: [{time, course_id, [type]}]}`; `course_id` = `_course/` filename or `research_work`.
+The current semester is shown first, upcoming after it, past ones collapse under "Past semesters" automatically.
+Semester labels render as **Season Year** (`Fall 2026` / `Осень 2026`) from `schedule.seasons` translations.
+
+### Update NIR / thesis tables
+- NIR reports: append rows to tables in `_i18n/en/nir.md` (see README for the row format); section headings are **Season Year** (`### Fall 2026`).
+- Theses: `_i18n/en/thesis.md`, sections by year (`### 2026`).
+
+### Conferences and home-page stats
+`scripts/update_data.py` (weekly via `refresh-data.yml`, or `python3 scripts/update_data.py` locally) rewrites deadlines/dates/venues for every conference with a `ccfddl:` key and the GitHub repo count in `_data/stats.yml`.
+To track a new conference add an entry with `ccfddl: <dir>/<file>` from https://github.com/ccfddl/ccf-deadlines/tree/main/conference; without the key the entry is manual (KDD, ACL).
+
+## Gotchas
+
+- The i18n plugin builds the site once per language; EN pages live at `/...`, RU at `/ru/...`.
+  `site.baseurl` is language-prefixed; `site.baseurl_root` is not — use `baseurl_root` for assets (images, JS).
+  In `seo.html`, image URLs are built from `site.url` + root path for the same reason.
+- SEO lives in `_includes/seo.html` (description, canonical, hreflang, Open Graph, JSON-LD incl. breadcrumbs) and the `<title>` template in `default.html`
+  (`<page> — <brand>`, strings under `site.seo` in `en.yml`/`ru.yml`).
+  A root stub with `untranslated: true` (nir, thesis, conferences, seminars, templates) and every blog post canonicalize their RU copy to the EN URL — remove the flag when RU content is added.
+- Every page has exactly one `<h1>`: layouts render the title as `h1.page-heading` (styled like h2), content pages start with a single `#` heading, list pages (`people.md`, `course.md`) carry an `h1.sr-only`.
+  Keep this when adding pages — Lighthouse/SEO and screen readers depend on it.
+- `_plugins/i18n_filter_cache.rb` clears Jekyll 4's `absolute_url` cache between the per-language builds; without it RU canonicals/sitemap point at EN URLs.
+- `{% t key %}` with a MISSING key fails the build (plugin 1.8 returns nil).
+  `page.title` may be a translation key (`titles.nir`, `people.x` — has a dot, no spaces) or a literal string (blog posts);
+  `_layouts/default.html` resolves it into `page_title` once, and `seo.html` reuses that — never call `{% t page.title %}` elsewhere.
+- People/course lookups are done by `page.url contains lecturer_id` string matching — keep IDs unique and never rename a person file without checking `lecturers:` fields in `_course/`.
+- `edit: true` in front matter shows the floating "edit on GitHub" button (`_includes/edit.html`).
+  It opens the file that actually rendered the page: `_i18n/<lang>/<path>` when that translation exists, `_i18n/en/<path>` when it does not (missing RU pages and bios fall back to EN, and linking a missing file gives a GitHub 404), the page's own file otherwise (blog posts).
+  Existence is checked against `site.i18n_files`, a `{path => true}` hash built by `_plugins/i18n_file_index.rb` — Liquid cannot read the filesystem.
+  Root stubs carry a `{% comment %}` telling editors that the text lives in `_i18n/{en,ru}/` — keep it when adding a stub.
+- `toc: true` + optional `toc_headings` enables the floating table of contents (`javascript/toc.js`).
+- Front matter defaults in `_config.yml` assign layouts by collection type — new files usually need no `layout:` key.
+- Tables are auto-wrapped for horizontal scroll by `table_scroll.js`; don't wrap them manually.
+- Images are NOT compressed manually.
+  The deploy workflow (`.github/workflows/jekyll.yml`, "Optimize images" step) resizes and compresses all jpg/png at build time; the repo keeps originals.
+- Do NOT delete unused images from `images/` — they are kept on purpose as an archive and may be reused later.
+- There is NO Bootstrap, jQuery, Font Awesome, academicons, or bulma-carousel — do not add CDN links back.
+  Navbar behavior is `javascript/navbar.js`; navbar structural CSS is `_sass/_bootstrap_shim.scss`.
+  Icons: `<i class="fa fa-NAME"></i>` / `<i class="ai ai-NAME"></i>` markup still works, but only for the classes defined in `_sass/_icons.scss` — to add a new icon, add its SVG there as a mask.
+- MathJax loads only on `layout: blog` pages or pages with `math: true`; mermaid only on `blog` layout or `mermaid: true` (see conditions in `_layouts/default.html`).
+- No inline `style="..."` in markup — every visual rule lives in `_sass/`.
+  Home page sections use dedicated classes in `_sass/_home.scss` (`.hero*`, `.stats*`, `.research-*`, `.tag-list`, `.fullwidth-figure`); person cards and social links are includes, never copy-pasted markup.
+- Responsive container widths come from the `$container-widths` map in `_sass/_variables.scss` — change breakpoint behavior there, not in per-file media queries.
+- EN and RU `index.md` must keep identical markup (only text differs, plus the `hero__title--sm` modifier on RU for the longer title).