fix(ci): remove NODE_AUTH_TOKEN, use OIDC provenance

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

Author: stephendolan

.github/workflows/release.yml

@@ -43,8 +43,6 @@ jobs:
 
       - name: Publish to npm
         run: npm publish --provenance --access public
-        env:
-          NODE_AUTH_TOKEN: ${{ secrets.NPM_TOKEN }}
 
       - name: Create GitHub Release
         uses: softprops/action-gh-release@v2