Add Sphinx documentation workflow

.github/workflows/sphinx.yml

@@ -0,0 +1,24 @@
+name: "Sphinx: Render docs"
+
+on: push
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+    permissions:
+      contents: write
+    steps:
+    - uses: actions/checkout@v4
+    - name: Build HTML
+      uses: ammaraskar/sphinx-action@master
+    - name: Upload artifacts
+      uses: actions/upload-artifact@v4
+      with:
+        name: html-docs
+        path: docs/build/html/
+    - name: Deploy
+      uses: peaceiris/actions-gh-pages@v3
+      if: github.ref == 'refs/heads/main'
+      with:
+        github_token: ${{ secrets.GITHUB_TOKEN }}
+        publish_dir: docs/build/html

docs/requirements.txt

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+myst-parser
+nbsphinx