Add support to preview a theme with a selected style

[bobbingwide]

Having added the Styles tab I now want to be able to support the preview function, that was developed in order to cache patterns, with the ability to select the style variant to be loaded.

As I wrote in https://blocks.wp-a2z.org/2022/11/01/styles-tab-for-themes/

On wordpress.org you can preview the style variations by clicking on a style variation displayed below the theme’s screenshot. Then you can preview the theme with that style. eg https://wp-themes.com/twentytwentytwo/?style_variation=pink

Requirement

• Preview a theme with a given style variation

Proposed solution

• oik-patterns will provide the logic to display the preview
• oik-themes will provide the link / button for the user choose.

Note: in the absence of an oik-patterns solution, the preview could be done for WordPress themes by using wordpress.org's solution as is. eg open wordpress.org's theme preview in a new window.