Migrate existing endpoints to the new structure

[MAILPOET-4207]

mailpoet/lib/Automation/Engine/Endpoints/Workflows/WorkflowsPostEndpoint.php

@@ -0,0 +1,26 @@
+<?php declare(strict_types = 1);
+
+namespace MailPoet\Automation\Engine\Endpoints\Workflows;
+
+use MailPoet\Automation\Engine\API\Endpoint;
+use MailPoet\Automation\Engine\API\Request;
+use MailPoet\Automation\Engine\API\Response;
+use MailPoet\Automation\Engine\Builder\CreateWorkflowController;
+
+class WorkflowsPostEndpoint extends Endpoint {
+  /** @var CreateWorkflowController */
+  private $createController;
+
+  public function __construct(
+    CreateWorkflowController $createController
+  ) {
+    $this->createController = $createController;
+  }
+
+  public function handle(Request $request): Response {
+    // TODO: validation
+    $data = $request->getBody();
+    $this->createController->createWorkflow($data);
+    return new Response();
+  }
+}