Exported JSON loses 'appearanceTools' abstraction

[pbking]

Description

When exporting the theme from the FSE the included theme.json is missing the appearanceTools attribute present in the theme's theme.json file and instead the attributes that abstracts are added instead.

Missing attribute present in original theme.json:
settings.appearanceTools

Among added attributes:
settings.color.custom
settings.color.customGradient
settings.color.link
settings.spacing.padding
settings.spacing.blockGap
settings.spacing.margin

I expect this is because the "appearanceTools" attribute is flipping all of those values "true" without the need to provide them. However it may be desirable to keep the original attribute in exported configuration so that if any additional attributes are enabled due to that value they are also included in the theme.

Step-by-step reproduction instructions

Activate a theme that defines settings.appearanceTools: true in the theme.json file.
Export that theme from the FSE using the hamburgerMenu>TOOLS>Export tool.
Compare the theme.json exported to the theme.json provided by the theme. Note that appearanceTools setting is absent while the values it represents are present.

Screenshots, screen recording, code snippet

No response

Environment info

No response

Please confirm that you have searched existing issues in the repo.

Yes

Please confirm that you have tested with all plugins deactivated except Gutenberg.

Yes

[scruffian]

Fixed by #39590