fix(metadata): apply YAML/XML attributes to virtual (method-backed) properties

[soyuka]

Summary

ExtractorPropertyMetadataFactory::create() short-circuited to handleNotFound() whenever the resource class did not declare a real PHP property matching the requested name:

if (
    !property_exists($resourceClass, $property) && !interface_exists($resourceClass)
    || null === ($propertyMetadata = $this->extractor->getProperties()[$resourceClass][$property] ?? null)
) {
    return $this->handleNotFound($parentPropertyMetadata, $resourceClass, $property);
}

YAML and XML mappings can legitimately declare virtual properties backed by methods — e.g. admin mapped to isAdmin() — and ExtractorPropertyNameCollectionFactory already surfaces those names. The guard silently dropped configured metadata (security expressions, descriptions, IRIs, …) for any such property. PHP #[ApiProperty] attributes worked because they bypass this factory.

The remaining null-coalesce on the extractor lookup already provides the correct fallback to handleNotFound() when the property is not in the extracted mapping, so the property_exists clause is redundant for real PHP properties and incorrect for virtual ones.

Truth table after the change:

Real PHP prop	Declared in YAML/XML	Before	After
yes	yes	extractor	extractor
yes	no	handleNotFound	handleNotFound (via ?? null)
no	yes	handleNotFound (bug)	extractor (fix)
no	no	handleNotFound	handleNotFound (via ?? null)

Only the third row changes.

Closes #8178

Test plan

• New unit test ExtractorPropertyMetadataFactoryTest::testCreateVirtualPropertyFromExtractor — fails before the fix with PropertyNotFoundException: Property "admin" of the resource class … not found., green after.
• src/Metadata/Tests/Property suite green (37/37).
• PropertyMetadataCompatibilityTest (YAML + XML) still green.