Generate custom JSON schema for dynamic setting

[charliermarsh]

Summary

If you paste in the TOML for our default configuration (from the docs), it's rejected by our JSON Schema:

It seems like the issue is with:

# Set the line length limit used when formatting code snippets in
# docstrings.
#
# This only has an effect when the `docstring-code-format` setting is
# enabled.
docstring-code-line-length = "dynamic"

Specifically, since that value uses a custom Serde implementation, I guess Schemars bails out? This PR adds a custom representation to allow "dynamic" (but no other strings):

This seems like it should work but I don't have a great way to test it.

Closes #9630.

[charliermarsh]

Oh actually, I was able to test it with https://www.jsonschemavalidator.net/.

Valid integer:

Valid string:

Invalid string:

[BurntSushi]

Thank you. :-)

[charliermarsh]

No prob!

[github-actions]

ruff-ecosystem results

Formatter (stable)

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Formatter (preview)

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