chore: import upstream snapshot with attribution

.github/workflows/star-history.yml

@@ -0,0 +1,49 @@
+name: Refresh Star History
+
+# Regenerates docs/star-history.svg from the repo's own star data.
+# Needed because GitHub restricts stargazer `starred_at` timestamps to a
+# repo's admins/collaborators, so star-history.com's anonymous embed no
+# longer renders. The repo's own token CAN read the data, so we self-host.
+#
+# Token: uses GITHUB_TOKEN by default. If that turns out not to have access
+# to starred_at, add a fine-grained PAT (Metadata: Read-only) as the repo
+# secret STAR_HISTORY_TOKEN and it will be used automatically.
+
+on:
+  schedule:
+    - cron: '0 3 * * 1'      # every Monday 03:00 UTC
+  workflow_dispatch:          # manual "Run workflow" button
+
+permissions:
+  contents: write
+
+concurrency:
+  group: star-history
+  cancel-in-progress: true
+
+jobs:
+  refresh:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+
+      - uses: actions/setup-python@v5
+        with:
+          python-version: '3.12'
+
+      - name: Regenerate star-history SVG
+        env:
+          GH_TOKEN: ${{ secrets.STAR_HISTORY_TOKEN || github.token }}
+        run: python3 tools/gen-star-history.py
+
+      - name: Commit if changed
+        run: |
+          if [[ -n "$(git status --porcelain docs/star-history.svg)" ]]; then
+            git config user.name  "github-actions[bot]"
+            git config user.email "41898282+github-actions[bot]@users.noreply.github.com"
+            git add docs/star-history.svg
+            git commit -m "chore: refresh star-history snapshot [skip ci]"
+            git push
+          else
+            echo "star-history.svg unchanged — nothing to commit."
+          fi