Need versioned (and updated) docs

[ptone]

Describe the bug

A number of changes between 0.3.0 and 0.5.0 of the package did not have corresponding doc updates.

One example:

https://google.github.io/adk-docs/tools/mcp-tools/#step-1-attach-the-mcp-server-to-your-adk-agent-via-mcptoolset

References an obsolete "from_server" class method

To Reproduce

Steps to reproduce the behavior:

1. Go to '...'
2. Click on '....'
3. See error

Expected behavior

A clear and concise description of what you expected to happen.

Screenshots

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Versions

• OS: [e.g. Windows, Mac, Linux]
• ADK version: 0.5.0
• Python version:

Additional context

Add any other context about the problem here.

[ptone]

May start sprinkling a few examples here in comments:

google/adk-python@9c2358e

and

https://github.com/google/adk-docs/blob/main/docs/tools/built-in-tools.md?plain=1#L62