feat: scaffold astro publishing pipeline

.gitea/workflows/verify.yml

@@ -0,0 +1,55 @@
+# Tier 3 gate and publication. The act-runner registration is stored in an
+# emptyDir: after a runner pod restart, re-register it before debugging CI.
+name: verify-and-publish
+
+on:
+  push:
+    branches: [main]
+  pull_request:
+
+jobs:
+  gate:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+        with:
+          fetch-depth: 0
+      - uses: actions/setup-node@v4
+        with:
+          node-version: 22
+          cache: npm
+      - run: npm install --package-lock=false --prefer-offline
+      - run: npm run lint
+      - run: ./.agents/scripts/gate.sh
+      - name: visual regression
+        run: |
+          npx playwright install --with-deps chromium
+          node .agents/scripts/visual-regression.mjs
+      - uses: actions/upload-artifact@v4
+        if: failure()
+        with:
+          name: screenshots
+          path: .agents/snapshots/diff/
+
+  publish:
+    if: github.ref == 'refs/heads/main'
+    needs: gate
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+      - uses: actions/setup-node@v4
+        with:
+          node-version: 22
+          cache: npm
+      - run: npm install --package-lock=false --prefer-offline
+      - run: npm run build
+      - name: Publish generated site to pages
+        run: |
+          git config user.name 'gitea-actions[bot]'
+          git config user.email 'gitea-actions[bot]@users.noreply.local'
+          git switch --orphan pages
+          git rm -rf .
+          cp -a dist/. .
+          git add --all
+          git commit -m 'chore: publish site'
+          git push --force origin HEAD:pages