Feat: add PHP 8.4 lazy ghost mapper + fix asymmetric visibility in ClassPropertiesExtractor

[Shelamkoff]

Summary

Fixes #551 — Cycle ORM v2 incompatible with PHP 8.4 asymmetric visibility.

This PR adds two fixes:

1. Hot-fix: ClassPropertiesExtractor misclassifies private(set) / protected(set) properties as PUBLIC_CLASS because isPublic() returns true for the read visibility. ClosureHydrator then skips Closure::bind() and the fallback @$entity->$prop = $value silently fails. The fix checks isPrivateSet() / isProtectedSet() (PHP 8.4) before classifying.

2. Lazy ghost mapper: LazyGhostMapper + LazyGhostEntityFactory — a drop-in alternative to Mapper + ProxyEntityFactory using PHP 8.4 native ReflectionClass::newLazyGhost(). Solves the asymmetric visibility bug, final class limitation, and (array) cast issues with private(set) property names.

Changes

Bug fix: ClassPropertiesExtractor

// Before:
$class = $property->isPublic() ? PropertyMap::PUBLIC_CLASS : $className;

// After:
$class = $property->isPublic() && !$this->hasRestrictedSet($property)
    ? PropertyMap::PUBLIC_CLASS
    : $className;

New files

File	Description
src/Mapper/LazyGhost/LazyGhostEntityFactory.php	Entity factory using newLazyGhost(), setRawValueWithoutLazyInitialization(), WeakMap for pending refs
src/Mapper/LazyGhostMapper.php	Mapper delegating to LazyGhostEntityFactory (same structure as Mapper)

Usage

use Cycle\ORM\Mapper\LazyGhostMapper;

$schema = new Schema([
    'user' => [
        SchemaInterface::ENTITY => User::class,
        SchemaInterface::MAPPER => LazyGhostMapper::class,
        // ...
    ],
]);

Why lazy ghosts over proxies

Problem	ProxyEntityFactory	LazyGhostEntityFactory
private(set) hydration	isPublic() misclassifies → silent failure	setRawValueWithoutLazyInitialization() bypasses all visibility
final classes	eval() subclass → RuntimeException	Ghost IS the original class
Data extraction	(array) cast mangles private(set) names	ReflectionProperty::getValue()
get_class()	Returns proxy class name	Returns real entity class

Test plan

• ClassPropertiesExtractorTest — 5 tests: public, private(set), protected(set), private properties + relation with asymmetric visibility
• LazyGhostEntityFactoryTest — 16 tests: create, upgrade, extractData, extractRelations, extractAll, lazy initializer resolution
• Verify existing tests still pass