Docs site poc (#346)

add docusaurus based docs site under /docs

.github/workflows/deploy-docs-site.yaml

@@ -0,0 +1,53 @@
+name: Deploy docs to gitHub pages
+
+on:
+  push:
+    branches:
+      - main
+      - docs-site-poc
+    paths:
+      - ".github/workflows/deploy-docs-site.yaml"
+      - "docs/**"
+  pull_request:
+
+jobs:
+  deploy:
+    runs-on: ubuntu-22.04
+    permissions:
+      contents: write
+    concurrency:
+      group: ${{ github.workflow }}-${{ github.ref }}
+    defaults:
+      run:
+        working-directory: docs
+    steps:
+      - uses: actions/checkout@v3
+
+      - name: Setup Node
+        uses: actions/setup-node@v3
+        with:
+          node-version: "16"
+
+      - name: Get yarn cache
+        id: yarn-cache
+        run: echo "YARN_CACHE_DIR=$(yarn cache dir)" >> "${GITHUB_OUTPUT}"
+
+      - name: Cache dependencies
+        uses: actions/cache@v3
+        with:
+          path: ${{ steps.yarn-cache.outputs.YARN_CACHE_DIR }}
+          key: ${{ runner.os }}-docs-${{ hashFiles('**/yarn.lock') }}
+          restore-keys: |
+            ${{ runner.os }}-docs-
+
+      - run: yarn install --frozen-lockfile
+      - run: yarn build
+
+      - name: Deploy
+        uses: peaceiris/actions-gh-pages@v3
+        if:
+          ${{ github.ref == 'refs/heads/main' || github.ref ==
+          'refs/heads/docs-site-poc' }}
+        with:
+          github_token: ${{ secrets.GITHUB_TOKEN }}
+          publish_dir: ./docs/build