ci: build docs

.github/workflows/docs.yml

@@ -0,0 +1,50 @@
+name: gen-doc
+
+on:
+  push:
+    branches:
+      - main
+  workflow_dispatch:
+
+permissions:
+  contents: read
+  pages: write
+  id-token: write
+
+concurrency:
+  group: "pages"
+  cancel-in-progress: false
+
+jobs:
+  deploy-doc:
+    environment:
+      name: github-pages
+      url: ${{ steps.deployment.outputs.page_url }}
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v3
+      - uses: ./.github/actions/libextism
+        env:
+          GITHUB_TOKEN: ${{ github.token }}
+
+      - name: Setup elan toolchain on Linux or macOS
+        if: matrix.os == 'ubuntu-latest' || matrix.os == 'macos-latest'
+        run: |
+          curl -O --location https://raw.githubusercontent.com/leanprover/elan/master/elan-init.sh
+          chmod u+x elan-init.sh
+          ./elan-init.sh -y --default-toolchain leanprover/lean4:nightly
+          echo "Adding location $HOME/.elan/bin to PATH..."
+          echo "$HOME/.elan/bin" >> $GITHUB_PATH
+
+      - run: lake -R -Kenv=dev build Extism:docs
+
+      - name: Setup Pages
+        uses: actions/configure-pages@v3
+      - name: Upload artifact
+        uses: actions/upload-pages-artifact@v2
+        with:
+          path: '.lake/build/docs'
+      - name: Deploy to GitHub Pages
+        id: deployment
+        uses: actions/deploy-pages@v2
+