Add npm publish workflow

.github/workflows/publish.yml

@@ -0,0 +1,20 @@
+name: Publish codex-lib to npmjs
+on:
+  release:
+    types: [published]
+jobs:
+  build:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+      - uses: actions/setup-node@v3
+        with:
+          node-version-file: '.nvmrc'
+          cache: "npm"
+          cache-dependency-path: "package-lock.json"
+          check-latest: false
+          registry-url: 'https://registry.npmjs.org'
+      - run: npm ci
+      - run: npm publish
+        env:
+          NODE_AUTH_TOKEN: ${{ secrets.NPM_TOKEN }}