bugfix: theme generator use selected theme colors

[ak4zh]

Linked Issue

Closes #1179
Issue was closed but not implemented as it was moved to #1142

Description

Theme generator will use the current selected theme colors as well as text-on color.

Changsets

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Checklist

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• This PR targets the dev branch (NEVER master)
• Documentation reflects all relevant changes
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[changeset-bot]

🦋 Changeset detected

Latest commit: d0f19b2

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 1 package

Name	Type
skeleton.dev	Patch

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Name	Status	Preview	Updated (UTC)
skeleton-docs	✅ Ready (Inspect)	Visit Preview	Aug 23, 2023 1:00pm

[ak4zh]

Seems this is not ready yet for review, and I don't know how to convert back to draft mode.
I will re-open later after discussing whether to implement it or leave to be taken care of on the Theme Generator overhaul.