Replace contrib.rocks URL with self-hosted SVG + weekly regen workflow

Approach:
- Store the contributor avatar grid as a real file at
  docs/source/_static/contributors.svg (committed).
- README references the in-repo raw URL, so rendering only depends on
  GitHub itself (no third-party image service at view time).
- .github/workflows/contributors.yml regenerates the SVG weekly via a
  scheduled workflow (Monday 06:00 UTC, plus manual workflow_dispatch).
  It uses actions/github-script with the GitHub REST contributors API
  to build the SVG inline, then opens a PR via peter-evans/create-pull-request
  when the file changes.
- No third-party runtime services; all third-party actions are pinned
  to commit SHA (matching existing repo conventions in zizmor.yml/welcome.yml).
- zizmor clean; all prek hooks pass on the modified files.

Rationale: contrib.rocks was found to stall/time out for this repo on
first request, and cached refreshes are slow/unreliable (2+ weeks per
upstream maintainer discussion). This approach delivers the originally
requested "weekly auto-triggered PR" workflow with no ongoing human
maintenance beyond approving the bot PR.

Made-with: Cursor

Author: drbenvincent

.github/workflows/contributors.yml

@@ -0,0 +1,116 @@
+name: Update contributors image
+
+on:
+  schedule:
+    # Every Monday at 06:00 UTC
+    - cron: "0 6 * * 1"
+  workflow_dispatch: {}
+
+permissions: {}
+
+jobs:
+  update:
+    name: Regenerate contributors.svg
+    runs-on: ubuntu-latest
+    permissions:
+      contents: write
+      pull-requests: write
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
+        with:
+          persist-credentials: false
+
+      - name: Generate contributors SVG
+        uses: actions/github-script@ed597411d8f924073f98dfc5c65a23a2325f34cd # v8.0.0
+        with:
+          script: |
+            const fs = require('fs');
+            const path = require('path');
+
+            // Layout: circular avatars in a grid, matching the visual style
+            // used by the main pymc repo README.
+            const AVATAR = 64;   // rendered diameter in px
+            const GAP = 8;       // spacing between avatars
+            const COLS = 12;     // avatars per row
+            const PAD = 4;       // outer padding so circles are not clipped
+            const BOT_PATTERN = /\[bot\]$|^dependabot$|^renovate$|^renovate-bot$/i;
+
+            core.info(`Fetching contributors for ${context.repo.owner}/${context.repo.repo}`);
+            const contributors = await github.paginate(
+              github.rest.repos.listContributors,
+              { owner: context.repo.owner, repo: context.repo.repo, per_page: 100 }
+            );
+            core.info(`Fetched ${contributors.length} contributor records (pre-filter)`);
+
+            const people = contributors.filter(
+              (c) => c && c.type === 'User' && c.login && !BOT_PATTERN.test(c.login)
+            );
+            core.info(`Rendering ${people.length} human contributors`);
+
+            const rows = Math.max(1, Math.ceil(people.length / COLS));
+            const width = PAD * 2 + COLS * AVATAR + (COLS - 1) * GAP;
+            const height = PAD * 2 + rows * AVATAR + (rows - 1) * GAP;
+
+            const xmlEscape = (s) =>
+              String(s).replace(/[&<>"']/g, (c) => ({
+                '&': '&amp;', '<': '&lt;', '>': '&gt;', '"': '&quot;', "'": '&#39;',
+              })[c]);
+
+            // Request a sized avatar from GitHub to keep the SVG small.
+            const avatarUrl = (c) => {
+              const base = (c.avatar_url || '').split('?')[0];
+              return base ? `${base}?s=${AVATAR * 2}` : '';
+            };
+
+            const cells = people.map((c, i) => {
+              const col = i % COLS;
+              const row = Math.floor(i / COLS);
+              const x = PAD + col * (AVATAR + GAP);
+              const y = PAD + row * (AVATAR + GAP);
+              const r = AVATAR / 2;
+              const cx = x + r;
+              const cy = y + r;
+              const clipId = `c${i}`;
+              const href = xmlEscape(`https://github.com/${c.login}`);
+              const img = xmlEscape(avatarUrl(c));
+              const title = xmlEscape(c.login);
+              return [
+                `  <a href="${href}" target="_blank" rel="noopener">`,
+                `    <title>${title}</title>`,
+                `    <clipPath id="${clipId}"><circle cx="${cx}" cy="${cy}" r="${r}" /></clipPath>`,
+                `    <image href="${img}" x="${x}" y="${y}" width="${AVATAR}" height="${AVATAR}" clip-path="url(#${clipId})" preserveAspectRatio="xMidYMid slice" />`,
+                `  </a>`,
+              ].join('\n');
+            }).join('\n');
+
+            const svg = [
+              `<svg xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" width="${width}" height="${height}" viewBox="0 0 ${width} ${height}" role="img" aria-label="CausalPy contributors">`,
+              `  <title>CausalPy contributors (${people.length})</title>`,
+              cells,
+              `</svg>`,
+              '',
+            ].join('\n');
+
+            const outPath = path.join('docs', 'source', '_static', 'contributors.svg');
+            fs.mkdirSync(path.dirname(outPath), { recursive: true });
+            fs.writeFileSync(outPath, svg);
+            core.info(`Wrote ${outPath} (${svg.length} bytes)`);
+
+      - name: Create pull request if changed
+        uses: peter-evans/create-pull-request@5f6978faf089d4d20b00c7766989d076bb2fc7f1 # v8.1.1
+        with:
+          token: ${{ secrets.GITHUB_TOKEN }}
+          commit-message: "Update contributors image"
+          title: "Update contributors image"
+          body: |
+            Automated refresh of `docs/source/_static/contributors.svg`.
+
+            Generated by `.github/workflows/contributors.yml` from the GitHub
+            contributors API. Bot accounts are filtered out.
+
+            Safe to merge once the preview looks right.
+          branch: bot/update-contributors
+          delete-branch: true
+          add-paths: docs/source/_static/contributors.svg
+          labels: documentation

README.md

@@ -170,4 +170,8 @@ Plans for the repository can be seen in the [Issues](https://github.com/pymc-lab
 
 ## Thanks to our contributors
 
-[![Contributors](https://contrib.rocks/image?repo=pymc-labs/CausalPy)](https://github.com/pymc-labs/CausalPy/graphs/contributors)
+<a href="https://github.com/pymc-labs/CausalPy/graphs/contributors">
+  <img src="https://raw.githubusercontent.com/pymc-labs/CausalPy/main/docs/source/_static/contributors.svg" alt="CausalPy contributors" />
+</a>
+
+The contributor image is regenerated weekly by a GitHub Actions workflow (`.github/workflows/contributors.yml`) that opens a PR when the contributor list changes.