ci: update GitHub Actions workflow for Node.js CI

Added `registry-url` to the setup-node step and `NPM_CONFIG_PROVENANCE` to the publish step in the GitHub Actions workflow for Node.js CI. This ensures that the workflow uses the correct npm registry and enables package provenance tracking for published packages.

.github/workflows/ci.yml

@@ -26,6 +26,7 @@ jobs:
         with:
           node-version: 20.x
           cache: "pnpm"
+          registry-url: "https://registry.npmjs.org/"
 
       # --- Install, build, and test.
       - run: pnpm install
@@ -44,3 +45,4 @@ jobs:
         run: pnpm publish:ci --registry https://registry.npmjs.org
         env:
           NODE_AUTH_TOKEN: ${{secrets.NPM_TOKEN}}
+          NPM_CONFIG_PROVENANCE: true