Mark built-in node visitors as @internal

src/NodeVisitor/EscaperNodeVisitor.php

@@ -29,6 +29,8 @@ use Twig\NodeTraverser;
 
 /**
  * @author Fabien Potencier <fabien@symfony.com>
+ *
+ * @internal
  */
 final class EscaperNodeVisitor implements NodeVisitorInterface
 {

src/NodeVisitor/MacroAutoImportNodeVisitor.php

@@ -23,6 +23,8 @@ use Twig\Node\Node;
 
 /**
  * @author Fabien Potencier <fabien@symfony.com>
+ *
+ * @internal
  */
 final class MacroAutoImportNodeVisitor implements NodeVisitorInterface
 {

src/NodeVisitor/OptimizerNodeVisitor.php

@@ -34,6 +34,8 @@ use Twig\Node\PrintNode;
  * optimizer mode.
  *
  * @author Fabien Potencier <fabien@symfony.com>
+ *
+ * @internal
  */
 final class OptimizerNodeVisitor implements NodeVisitorInterface
 {

src/NodeVisitor/SafeAnalysisNodeVisitor.php

@@ -23,6 +23,9 @@ use Twig\Node\Expression\NameExpression;
 use Twig\Node\Expression\ParentExpression;
 use Twig\Node\Node;
 
+/**
+ * @internal
+ */
 final class SafeAnalysisNodeVisitor implements NodeVisitorInterface
 {
     private $data = [];

src/NodeVisitor/SandboxNodeVisitor.php

@@ -28,6 +28,8 @@ use Twig\Node\SetNode;
 
 /**
  * @author Fabien Potencier <fabien@symfony.com>
+ *
+ * @internal
  */
 final class SandboxNodeVisitor implements NodeVisitorInterface
 {