Review of "Running MaxText at Scale with XPK" guide

[melissawm]

Description

Follow-up to #2238.

This PR mostly fixes some syntax and rendering issues for the "Running MaxText at Scale with XPK" guide. It includes

• Replacing a text-based diagram with an SVG;
• Adding some admonition-style blocks for notes and important content in the guide;
• Enabling the "copybutton" Sphinx extension, which adds a nice element to each code-block allowing the reader to copy the code-block contents directly, for convenience;
• Addressing @kyle-meggs ' s suggestion from docs: Improve guide for multi-host training with XPK #2238 (comment);
• Some other quick fixes to prevent the Read The Docs build from failing (might be redundant with some of the work in Review Data Input Pipeline guides #2266 )

Tests

The documentation pages were successfully built locally.

Checklist

Before submitting this PR, please make sure (put X in square brackets):

• I have performed a self-review of my code.
• I have necessary comments in my code, particularly in hard-to-understand areas.
• I have run end-to-end tests tests and provided workload links above if applicable.
• I have made or will make corresponding changes to the doc if needed.

[parambole]

Left a few comments on formatting when viewed.

[melissawm]

I addressed this on the chat, but here's the same message for clarity:

Unfortunately, the GitHub markdown parser is quite limited, and some of the functionality we use to create nice formatting and display of text, code and images (as well as anchor linking and reference labels) will not work on plain GitHub. Usually, when projects have a ReadTheDocs site, the primary information delivery method is the generated HTML pages shown on the site, and not the source markdown files on GitHub.

If the priority is to have the source files be GitHub-compatible, I will have to remove some of the functionality from the readthedocs pages. I think this is a discussion worth having with the team to make sure we are aligned.

[github-actions]

This PR has been automatically marked as stale because it has not had recent activity. It will be closed soon if no further activity occurs. Thank you for your contributions.

[github-actions]

This PR was closed because it has been inactive for a while. Please reopen it if you are still working on it.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.

📢 Thoughts on this report? Let us know!

[melissawm]

This can now be closed as all relevant changes have been applied upstream. Thanks!