gh-139588: Docs: Convert the execution model "textual" diagram to a visual diagram

[adorilson]

It prevents LaTeX PDF build error: Too deeply nested. (Regression from #139509.).

Besides, it also makes the diagram richer.

It is an alternative to #140709.

#139588: Docs: Convert the execution model "textual" diagram to a visual diagram

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📚 Documentation preview 📚: https://cpython-previews--140721.org.readthedocs.build/

• Issue: make dist-pdf is broken #139588

[StanFromIreland]

Note that the error has now been fixed by the other PR.

[StanFromIreland]

How does this work with translations? Is it extracted by the gettext builder?

[rffontenelle]

gettext builder extracts the current text for translation, but the product of this pull request is not extracted for translation. (just tested)

[StanFromIreland]

Thanks for testing, Rafael.

As such, I am -0 on this, although we could keep the textual ones just for translations (instead of the graphic) using the .. only:: translation tag I added recently.

[rffontenelle]

The best would be to have this graphic but the labels translated, but I don't even know if it is possible.

[StanFromIreland]

It also breaks on EPUB:

WARNING: dot command 'dot' cannot be run (needed for graphviz output), check the graphviz_dot setting

[adorilson]

It also breaks on EPUB:

WARNING: dot command 'dot' cannot be run (needed for graphviz output), check the graphviz_dot setting

What exactly command did you use to get this? And what SO?

I've tried on Ubuntu, but I didn't get this warning or any other indication that the build will fail. However, the generated EPUB file is broken.

[StanFromIreland]

See the CI: https://github.com/python/cpython/actions/runs/18887326277/job/53905948098?pr=140721