ci: surface pkg-pr-new main install info in run summary

Author: cameroncooke

.github/workflows/ci.yml

@@ -52,5 +52,32 @@ jobs:
         run: npx pkg-pr-new publish --comment=update
 
       - name: Publish preview package for main
+        id: pkg_pr_new_main
         if: github.event_name == 'push' && github.ref == 'refs/heads/main'
-        run: npx pkg-pr-new publish --comment=off
+        run: |
+          set -euo pipefail
+          npx pkg-pr-new publish --comment=off --json=pkg-pr-new-main.json
+
+      - name: Summarize pkg.new output for main
+        if: github.event_name == 'push' && github.ref == 'refs/heads/main' && always()
+        run: |
+          {
+            echo "## pkg.new preview for main"
+            echo
+            if [ -f pkg-pr-new-main.json ]; then
+              echo "Install commands and preview links:"
+              echo '```text'
+              jq -r '.. | strings | select(test("pkg\\.pr\\.new|pkg\\.new|npm (i|install) "))' pkg-pr-new-main.json | sort -u
+              echo '```'
+            else
+              echo "No pkg.new JSON output file was produced."
+            fi
+          } >> "$GITHUB_STEP_SUMMARY"
+
+      - name: Upload pkg.new metadata for main
+        if: github.event_name == 'push' && github.ref == 'refs/heads/main' && always()
+        uses: actions/upload-artifact@v4
+        with:
+          name: pkg-pr-new-main-${{ github.sha }}
+          path: pkg-pr-new-main.json
+          if-no-files-found: warn