feat (blueprint): adds WordPress Playground blueprint for live demo

[firestar300]

Introduces a WordPress Playground configuration to allow users to preview the plugin instantly. This includes a blueprint that installs the plugin and creates a demo page, along with a "Test with WordPress Playground" badge in the README.

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Note

Low Risk
Adds only demo/packaging assets (Playground config + README link) and does not modify runtime plugin behavior.

Overview
Adds a WordPress Playground blueprint (.wordpress-org/blueprints/blueprint.json) that installs and activates the plugin from the 1.1.1 tag, logs in, and runs a PHP step to create/publish a demo page prepopulated with blockparty/tabs markup.

Updates README.md to include a “Test with WordPress Playground” badge linking to the hosted Playground instance using this blueprint.

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Cursor Bugbot has reviewed your changes and found 1 potential issue.

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Blueprint references non-existent plugin version tag

High Severity

The ref field in the installPlugin step is set to "1.1.1", but the plugin's current version is 1.1.0 — no 1.1.1 tag exists in the repository. This causes the WordPress Playground blueprint to fail when trying to install the plugin, making the entire live demo non-functional.

 

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