Add build-docs workflow

Author: microbit-grace

.github/workflows/build-docs.yml

@@ -0,0 +1,39 @@
+name: build-docs
+on:
+  release:
+    types: [created]
+  push:
+    branches:
+      - "**"
+    tags:
+      - "**"
+jobs:
+  build:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+      - name: Setup Pages
+        uses: actions/configure-pages@v5
+      - run: npm ci
+      - name: Build docs
+        run: npm run docs
+      - name: Upload artifact
+        uses: actions/upload-pages-artifact@v3
+        with:
+          path: ./docs/build
+
+  deploy:
+    if: ${{ startsWith(github.ref, 'refs/tags/') }}
+    permissions:
+      pages: write
+      id-token: write
+    environment:
+      name: github-pages
+      url: ${{ steps.deployment.outputs.page_url }}
+    runs-on: ubuntu-latest
+    needs: build
+    steps:
+      - name: Deploy to GitHub Pages
+        id: deployment
+        uses: actions/deploy-pages@v4