PHP-only blocks: Pass all metadata from PHP registration to the client - #73556

What

Solves #73499: PHP-only blocks with auto_register support now pass all metadata from the PHP registration, like title.

Why

When registering PHP-only blocks with 'supports' => array( 'auto_register' => true ), the block name was used as the title instead of the PHP-defined title; other metadata (icon, category, description, etc.) was completely ignored. This made it impossible for developers to customize how their auto-registered blocks appear in the inserter

How

• Spread all bootstrapped block type metadata when auto-registering blocks in JS
• Keep fallback to block name for title if not provided
• Add a set of tests to verify that metadata is successfully provided to the client registration

Testing Instructions

1. Register a PHP-only block with custom metadata:

   register_block_type( 'my/block', array(
       'title'       => 'My Custom Title',
       'icon'        => 'admin-generic',
       'category'    => 'widgets',
       'description' => 'My block description',
       'keywords'    => array( 'test' ),
       'render_callback' => fn() => '<p>Hello</p>',
       'supports'    => array( 'auto_register' => true ),
   ) );

2. Open the block inserter and search for "My Custom Title"
3. Verify the block appears with the custom title, icon, and in the correct category

Before	After