Add internal annotations

lib/Worker/Internal/Job.php

@@ -4,6 +4,7 @@ namespace Amp\Parallel\Worker\Internal;
 
 use Amp\Parallel\Worker\Task;
 
+/** @internal */
 class Job {
     /** @var string */
     private $id;

lib/Worker/Internal/PooledWorker.php

@@ -6,6 +6,7 @@ use Amp\Parallel\Worker\Task;
 use Amp\Parallel\Worker\Worker;
 use Amp\Promise;
 
+/** @internal */
 class PooledWorker implements Worker {
     /** @var callable */
     private $push;

lib/Worker/Internal/TaskFailure.php

@@ -7,6 +7,7 @@ use Amp\Parallel\Worker\TaskError;
 use Amp\Parallel\Worker\TaskException;
 use Amp\Promise;
 
+/** @internal */
 class TaskFailure extends TaskResult {
     const PARENT_EXCEPTION = 0;
     const PARENT_ERROR = 1;

lib/Worker/Internal/TaskResult.php

@@ -4,6 +4,7 @@ namespace Amp\Parallel\Worker\Internal;
 
 use Amp\Promise;
 
+/** @internal */
 abstract class TaskResult {
     /** @var string Task identifier. */
     private $id;

lib/Worker/Internal/TaskSuccess.php

@@ -5,6 +5,7 @@ namespace Amp\Parallel\Worker\Internal;
 use Amp\Promise;
 use Amp\Success;
 
+/** @internal */
 class TaskSuccess extends TaskResult {
     /** @var mixed Result of task. */
     private $result;