Document stability of undocumented classes

Bug: T248399
Change-Id: I9445d5c0753f7272c3d22d66b8824f8a95b86d41

includes/Constants.php

@@ -6,6 +6,8 @@ use FatalError;
 /**
  * A namespace for Vector constants for internal Vector usage only. **Do not rely on this file as an
  * API as it may change without warning at any time.**
+ * @package Vector
+ * @internal
  */
 final class Constants {
 	/**

includes/Hooks.php

@@ -17,6 +17,8 @@ use User;
  *
  * Hook handler method names should be in the form of:
  *	on<HookName>()
+ * @package Vector
+ * @internal
  */
 class Hooks {
 	/**

includes/SkinVector.php

@@ -29,6 +29,8 @@ use Vector\Constants;
  * Skin subclass for Vector
  * @ingroup Skins
  * Skins extending SkinVector are not supported
+ * @package Vector
+ * @internal
  */
 class SkinVector extends SkinMustache {