test: temporary e2e run for the draft Actions guide (do not merge)

.github/workflows/guides-e2e-screenshots.yml

@@ -0,0 +1,29 @@
+# TEMPORARY: end-to-end check for the draft /guides Actions guide (PR #1024).
+# Mirrors the guide's workflow. Delete this branch after the run.
+on: pull_request
+
+permissions:
+  contents: read
+  pull-requests: write
+
+jobs:
+  screenshots:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+      - name: Write a test screenshot
+        run: |
+          mkdir -p shots
+          python3 -c "
+          import zlib, struct
+          w, h = 800, 400
+          raw = b''.join(b'\x00' + bytes([31, 41, 55]) * w for _ in range(h))
+          def chunk(t, d): return struct.pack('>I', len(d)) + t + d + struct.pack('>I', zlib.crc32(t + d))
+          png = b'\x89PNG\r\n\x1a\n' + chunk(b'IHDR', struct.pack('>IIBBBBB', w, h, 8, 2, 0, 0, 0)) + chunk(b'IDAT', zlib.compress(raw)) + chunk(b'IEND', b'')
+          open('shots/ci-e2e.png', 'wb').write(png)
+          "
+      - run: npm install -g @buildinternet/uploads
+      - run: uploads put ./shots/*.png --pr ${{ github.event.pull_request.number }}
+        env:
+          UPLOADS_TOKEN: ${{ secrets.UPLOADS_TOKEN }}
+          GH_TOKEN: ${{ github.token }}