feat(theme): Add lilac_mist (sandyg6)

[sandyg6]

Description

• Added a new color palette feature to themes.

Checks

• Adding quotes?
  • Make sure to include translations for the quotes in the description (or another comment) so we can verify their content.
• Adding a language or a theme?
  • If is a language, did you edit _list.json, _groups.json and add languages.json?
  • If is a theme, did you add the theme.css?
    • Also please add a screenshot of the theme, it would be extra awesome if you do so!
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Closes #

[Miodec]

Text must be white or black (can be tinted). Please update.

[sandyg6]

DESCRIPTION:

• Updated new colors to the theme lilac_mist

[github-actions]

This PR is stale. Please trigger a re-run of the PR check action.

[Miodec]

Switch the sub and text color around, and also diffrentiate somehow between (new) sub and main. That way text color will be darker.

[sandyg6]

DESCRIPTION:

Updated new colors to the theme lilac_mist

[Miodec]

Errors have 0 contrast compared to typed text.

[sandyg6]

Description:

• Newly updated error color
  

[Miodec]

Thanks