chore: add weekly link-rot GitHub Action

- Saturday cron plus manual dispatch; gh-api liveness check with archived and 12-month-stale flags
- opens or updates a `link-rot` issue only when a dead link exists (archived and stale are review hints, not auto-removed)
- reusable .github/scripts/link-check.sh runs locally too; ignore the report.md artifact

Author: bidual

.github/scripts/link-check.sh

@@ -0,0 +1,48 @@
+#!/usr/bin/env bash
+# Link-rot + staleness check for the entry list.
+# Verifies every entry repo is reachable; flags archived and >12-month-stale repos.
+# Runs locally (macOS/Linux) and in CI. Uses only `gh` (no jq/curl dependency).
+# Exits nonzero only when a dead link exists — archived/stale are review hints.
+set -uo pipefail
+
+README="${1:-README.md}"
+today=$(date -u +%F)
+
+# 12-month cutoff as YYYY-MM-DD (ISO dates sort lexically == chronologically).
+if date -u -d '12 months ago' +%F >/dev/null 2>&1; then
+  cutoff=$(date -u -d '12 months ago' +%F)   # GNU date (CI)
+else
+  cutoff=$(date -u -v-12m +%F)               # BSD date (macOS)
+fi
+
+# Extract entry repos (owner/repo) from list-item GitHub links.
+repos=$(grep -oE '^- \[[^]]+\]\(https://github.com/[^)]+\)' "$README" \
+  | grep -oE 'github\.com/[^/)#]+/[^/)#]+' | sed 's#github\.com/##' | sort -u)
+total=$(printf '%s\n' "$repos" | grep -c .)
+
+dead=""; n_dead=0
+arch=""; n_arch=0
+stale=""; n_stale=0
+
+for r in $repos; do
+  if ! out=$(gh api "repos/$r" --jq '(.archived|tostring)+" "+(.pushed_at|.[0:10])' 2>/dev/null); then
+    dead="${dead}- \`${r}\`"$'\n'; n_dead=$((n_dead + 1)); continue
+  fi
+  a=${out%% *}; p=${out##* }
+  [ "$a" = "true" ] && { arch="${arch}- \`${r}\` (pushed ${p})"$'\n'; n_arch=$((n_arch + 1)); }
+  [[ "$p" < "$cutoff" ]] && { stale="${stale}- \`${r}\` (pushed ${p})"$'\n'; n_stale=$((n_stale + 1)); }
+done
+
+{
+  echo "## Link-rot report — ${today}"
+  echo
+  echo "- Checked: ${total} entry links"
+  echo "- Dead: ${n_dead}"
+  echo "- Archived: ${n_arch}"
+  echo "- Stale (>12 months): ${n_stale}"
+  [ "$n_dead"  -gt 0 ] && { echo; echo "### ❌ Dead links (fix or remove)"; printf '%s' "$dead"; }
+  [ "$n_arch"  -gt 0 ] && { echo; echo "### 📦 Archived (review — a frozen model repo is often fine)"; printf '%s' "$arch"; }
+  [ "$n_stale" -gt 0 ] && { echo; echo "### 🕸 Stale >12 months (review)"; printf '%s' "$stale"; }
+} | tee report.md
+
+[ "$n_dead" -eq 0 ]

.github/workflows/link-rot.yml

@@ -0,0 +1,40 @@
+name: link-rot
+
+on:
+  schedule:
+    - cron: '0 0 * * 6'   # Saturday 00:00 UTC (Sat 09:00 KST)
+  workflow_dispatch: {}
+
+permissions:
+  contents: read
+  issues: write
+
+jobs:
+  check:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+
+      - name: Check entry links
+        id: check
+        env:
+          GH_TOKEN: ${{ github.token }}
+        run: |
+          if bash .github/scripts/link-check.sh README.md; then
+            echo "dead=0" >> "$GITHUB_OUTPUT"
+          else
+            echo "dead=1" >> "$GITHUB_OUTPUT"
+          fi
+
+      - name: Report dead links to an issue
+        if: steps.check.outputs.dead == '1'
+        env:
+          GH_TOKEN: ${{ github.token }}
+        run: |
+          gh label create link-rot --color B60205 --description "Dead or rotten entry link" --force
+          existing=$(gh issue list --label link-rot --state open --json number --jq '.[0].number // empty')
+          if [ -n "$existing" ]; then
+            gh issue comment "$existing" --body-file report.md
+          else
+            gh issue create --title "Link rot detected" --label link-rot --body-file report.md
+          fi

.gitignore

@@ -1,2 +1,3 @@
 .DS_Store
 .gstack/
+report.md