ci: ReadTheDocs deploy demo

Author: attakei

.readthedocs.yaml

@@ -6,9 +6,11 @@ build:
     python: '3.12'
   commands:
     - pip install uv
-    - uv sync --frozen
+    - uv sync --frozen --all-extras
     - uv run sphinx-apidoc -f -e -T -o=docs/api/ ./oembedpy
-    - uv run sphinx-build -b dirhtml docs $READTHEDOCS_OUTPUT/html
+    - uv run sphinx-build -b dirhtml docs docs/_build/dirhtml
+    - uv run mkdocs build
+    - mv docs/_build/dirhtml $READTHEDOCS_OUTPUT/html
 
 # Optionally build your docs in additional formats such as PDF and ePub
 formats: []