Generate top-level and individual API reference docs for all SDK clients

[arandito]

Description

This PR adds documentation generation for all AWS clients in the aws-sdk-python repo. Users can either generate a single top-level documentation site for all clients or independently for individual clients (see Testing).

Documentation is built using:

• Material for Mkdocs - The Markdown theme to generate the static html files for the documentation site
• mkdocstrings - Auto-documents python modules using Markdown docstrings
• griffe - Parses client packages to generate stub files used by mkdocstrings to generate documentation

Testing

For top-level client docs, execute these commands in the root level of this repo. For individual client documentation, execute these commands in each client's directory.

# Install docs dependencies
make docs-install

# Build static HTML to site/
make docs

# Serve documentation locally to port 8000
make docs-serve

# Clean up artifacts
make docs-clean

By submitting this pull request, I confirm that you can use, modify, copy, and redistribute this contribution, under the terms of your choice.

[jonathan343]

Thanks Antonio, this is a great start. I've left some initial comments around the configuration of the documentation. I'll get to the generation scripts later tonight, but wanted to comment on what I've seen so far.

Additionally, I have some high-level comment around the top-level clients page:

1. We need to remove the None links and replace them with individual client links.
2. The individual client links throw 404 - Not found.
3. We need to avoid including folders like .ruff_cache

[jonathan343]

More (mostly minor) comments after reviewing the generate_doc_stubs.py script. I know some of the navbar stuff is WIP, so I'll probably wait to review that file