feat: Apply Libadwita-style theme to QT apps

[dajix350]

Feature description

It would help unify the look of a user's desktop if you allowed theming QT apps as well. In an effort to do this, I installed KvLibadwaita, but as expected it didn't adopt the Gradience colour scheme. Can you make it generate a Kvantum theme based on KvLibadwaita but with your colour scheme, similar to the Firefox GNOME style plugin?

Additional Context

No response

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[github-actions]

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[daudix]

Duplicate of GradienceTeam/Plugins#15 and GradienceTeam/Plugins#4