fix(shared): prevent cross-type equality in EntityId::equals (LSP)

src/Shared/DDD/Model/EntityId.php

@@ -23,6 +23,6 @@ abstract readonly class EntityId implements \Stringable, Equatable
     #[\Override]
     public function equals(mixed $other): bool
     {
-        return $other instanceof self && $this->value === $other->value;
+        return $other instanceof static && $this->value === $other->value;
     }
 }

tests/Unit/Shared/DDD/EntityIdTest.php

@@ -33,4 +33,28 @@ describe('EntityId', function (): void {
         {
         })->toThrow(\DomainException::class);
     });
+
+    it('correctly compares equality for identical and distinct instances', function (): void {
+        // GIVEN
+        $classA1 = new DummyEntityIdA('uuid-1');
+        $classA2 = new DummyEntityIdA('uuid-1');
+        $classA3 = new DummyEntityIdA('uuid-2');
+        $classB  = new DummyEntityIdB('uuid-1');
+
+        // WHEN & THEN
+        expect($classA1->equals($classA2))->toBeTrue()
+            ->and($classA1->equals($classA3))->toBeFalse()
+            ->and($classA1->equals($classB))->toBeFalse()
+            ->and($classB->equals($classA1))->toBeFalse()
+            ->and($classA1->equals('uuid-1'))->toBeFalse()
+            ->and($classA1->equals(null))->toBeFalse();
+    });
 });
+
+final readonly class DummyEntityIdA extends EntityId
+{
+}
+
+final readonly class DummyEntityIdB extends EntityId
+{
+}