Make client examples workspaces to reflect package code

[LucaButBoring]

Converts the client example packages into workspace folders so that they actually use the code in the repository instead of attempting to install mcp from PyPI. Also makes some minor tweaks to the chatbot example so it starts when run through uv.

The server examples are already set up as workspaces, so this was likely just an oversight.

Motivation and Context

I've wasted time on multiple occasions as a result of running the auth client example to debug auth flows, only to discover it's using the published version of the package instead of the code in the repository.

How Has This Been Tested?

Ran the auth client example and confirmed it works; ensured running the client does not create a dedicated .venv.

Breaking Changes

N/A

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)
• Documentation update

Checklist

• I have read the MCP Documentation
• My code follows the repository's style guidelines
• New and existing tests pass locally
• I have added appropriate error handling
• I have added or updated documentation as needed

Additional context