Missing definition for header property in library/component schema

Problem/Motivation

I have a SDC component with the following in the definition (MY_COMPONENT.component.yml):

libraryOverrides:
  header: true

This triggered the following error after updating to Drupal 11.4.0:

Drupal\Core\Render\Component\Exception\InvalidComponentException: In component MY_MODULE.MY_COMPONENT: [library] The property header is not defined and the definition does not allow additional properties in Drupal\Core\Theme\Component\ComponentValidator->validateDefinition() (line 153 of core/lib/Drupal/Core/Theme/Component/ComponentValidator.php).

Steps to reproduce

1. Create a component with the libraryOverrides.header property.
2. Use the component on some page.
3. Open the page.

Background

The header property is documented here: https://www.drupal.org/docs/develop/creating-modules/adding-assets-css-j...

Proposed resolution

I adjusted the schema for libraries by adding the following to property definitions:

"header": {
  "type": "boolean"
},

The relevant one seems to be under core/assets/schemas/v1/metadata-full.schema.json > properties/library/properties.
If that's correct, the error might apply to any library definition, not just components.

Tracing the definition, I started with "libraryOverrides", which is defined in core/assets/schemas/v1/metadata.schema.json. It references #/$defs/LibraryDefinition/, so I added the the above to its properties first, but it didn't fix the issue. I would still add it for consistency.

Remaining tasks

1. Review the patch.
2. Add a test for library/component schema.
3. Clarify where the difference between "library" (metadata-full.schema.json) and "LibraryDefinition" (metadata.schema.json) is.

User interface changes

None

Introduced terminology

None

API changes

None

Data model changes

None

Release notes snippet

Corrected definition for header property in library schema .