ci: Add push trigger for main branch and remove explicit npm registry URL and auth token from publish workflow.

.github/workflows/publish.yml

@@ -1,6 +1,8 @@
 name: Publish Package
 
 on:
+  push:
+    branches: [main]
   release:
     types: [created]
   workflow_dispatch:
@@ -17,9 +19,6 @@ jobs:
       - uses: actions/setup-node@v4
         with:
           node-version: '20'
-          registry-url: 'https://registry.npmjs.org'
       
       - run: npm ci
       - run: npm publish --provenance --access public
-        env:
-          NODE_AUTH_TOKEN: ${{ secrets.NPM_TOKEN }}