fix(ci): drop registry-url from setup-node so wasm publish uses OIDC

The publish step failed with a confusing 404 from registry.npmjs.org
because actions/setup-node@v4 with registry-url auto-writes

  //registry.npmjs.org/:_authToken=${NODE_AUTH_TOKEN}
  always-auth=true

into .npmrc. With NODE_AUTH_TOKEN unset (we removed it for Trusted
Publishing) npm sends an empty bearer token instead of falling back
to OIDC, and the registry rejects it as 404 / no permission.

Per npm's Trusted Publishing guidance, npm publish should run with
no token or _authToken settings. Drop registry-url so setup-node
leaves .npmrc untouched and npm can negotiate OIDC.

.github/workflows/publish-wren-core-wasm.yml

@@ -57,9 +57,14 @@ jobs:
       - name: Setup Node.js
         uses: actions/setup-node@v4
         with:
-          # Trusted Publishing requires Node.js >= 22.14.0; pin to 24 (latest LTS line)
+          # Trusted Publishing requires Node.js >= 22.14.0; pin to 24 (latest LTS line).
+          # Intentionally do NOT pass registry-url here: setup-node would auto-write
+          # an .npmrc containing
+          #   //registry.npmjs.org/:_authToken=${NODE_AUTH_TOKEN}
+          #   always-auth=true
+          # which prevents npm from falling back to OIDC, so Trusted Publishing
+          # fails with a confusing 404 even when correctly configured on npm.
           node-version: 24
-          registry-url: https://registry.npmjs.org
 
       - name: Ensure npm meets Trusted Publishing requirement (>= 11.5.1)
         run: npm install -g npm@latest