Add Live Preview button support to the plugin page

[masteradhoc]

Is your enhancement related to a problem? Please describe.

## Summary

Enable the Live Preview button on the plugin's WordPress.org plugin directory page by ensuring the existing blueprint is properly referenced and recognized by the Plugin Directory.

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## Background

WordPress.org plugin pages support a Live Preview button that launches a [WordPress Playground](https://wordpress.org/playground/) instance pre-configured via a blueprint.json file. This allows users to try the plugin instantly, directly in the browser, without needing to install anything.

A working example of this can be seen on the [Performance Lab plugin page](https://wordpress.org/plugins/performance-lab/), which shows the Live Preview button alongside the Download button.

The blueprint for this plugin has already been created and seems to work. The Live Preview button simply needs to be activated/surfaced on the plugin's WordPress.org listing page.

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## Steps to Activate

1. Log in to your WordPress.org account
2. Go to your plugin’s Advanced page
3. Scroll to “Toggle Live Preview”
4. Set the preview to “public”

Proposed Solution

The plugin page should display a Live Preview button (next to the Download button), identical to how it appears on:
👉 https://wordpress.org/plugins/performance-lab/

Clicking the button should launch a Playground instance with the plugin pre-installed and configured as defined in the existing blueprint.

Designs

Currently two-factor:

Preview of performance-lab:

Describe alternatives you've considered

No response

Please confirm that you have searched existing issues in this repository.

Yes

[masteradhoc]

@jeffpaul @kasparsd could anyone of you check this? :)

[jeffpaul]

Done.