fix : fix MCP create-task tool crashing on task creation

CreateTaskTool called nonexistent findMaxNumberByProject instead of
findMaxNumberByProjectForUpdate. Also removed FOR UPDATE clause from the
query as PostgreSQL does not support it with aggregate functions.

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

src/Mcp/Tool/Task/CreateTaskTool.php

@@ -54,7 +54,7 @@ class CreateTaskTool
         $task = new Task();
         $task->setProject($project);
         $task->setTitle($title);
-        $task->setNumber($this->taskRepository->findMaxNumberByProject($project) + 1);
+        $task->setNumber($this->taskRepository->findMaxNumberByProjectForUpdate($project) + 1);
 
         if (null !== $description) {
             $task->setDescription($description);