docs: update menu at ReadTheDocs

docs: update examples

chore: update AI instructions

chore: update AI instructions

docs: improve left menu at ReadTheDocs

docs: add okama.symbols_in_namespace and okama.search to menu in ReadTheDocs

style: flake8

docs: add new methods to ReadTheDocs

style: black formatting

docs: update examples

docs: update 01 howto.ipynb

docs: update index.rst

docs: add okama.namespaces.rst

docs: update requirements.txt for ReadTheDocs

chore: update connect