Broaden write-only property check to all objects, not just ArrayAccess

Objects like Threaded support array operations without implementing
ArrayAccess. Use isObject() instead of checking for ArrayAccess
specifically, so that appending to any object property via array
syntax is correctly treated as a read.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Author: phpstan-bot

src/Node/ClassStatementsGatherer.php

@@ -20,7 +20,6 @@
 use PHPStan\Node\Property\PropertyWrite;
 use PHPStan\Reflection\ClassReflection;
 use PHPStan\ShouldNotHappenException;
-use PHPStan\Type\ObjectType;
 use PHPStan\Type\TypeUtils;
 use ReflectionProperty;
 use function count;
@@ -209,7 +208,7 @@ private function gatherNodes(Node $node, Scope $scope): void
 				$propertyType = $scope->getType($propertyFetch);
 				if (
 					!$propertyType->isArray()->yes()
-					&& (new ObjectType(\ArrayAccess::class))->isSuperTypeOf($propertyType)->yes()
+					&& $propertyType->isObject()->yes()
 				) {
 					$this->propertyUsages[] = new PropertyRead($propertyFetch, $scope);
 				}