Mostieri/address further tech review comments

[mariostieriansys]

Closes #11

Address further tech review comments:

1. Readme image was broken since I got the documentation from PyEnSight, which is using Sphinx to render the RST. I sorted it out pointing to the image in the PyEnSight folder. While this might be an issue in the future, we will likely overhaul the branch README soon.
2. I included the exts folder in the doc-style action options
3. I changed the metadata, since the extension is only supposed to run on Python 3.10 (specifically the Omniverse Python 3.10)
4. Main change of the PR. We don't run sphinx as part of a build, so the numpydoc style was not enforced. I tried to enforce it via flake8, but for some reason it wasn't finding issues on the exts content. I ended up adding a pre-commit hook specifically designed for the numpydoc validation. Main trouble is that it is quite pedantic, and the suggestions in the docs to set the configuration in the pyproject toml just don't work. I had to add the exclusions in the precommit configuration and several ignore statements in the code. I hope to find a better alternative for the future

[RobPasMue]

LGTM!