结构大修改，改成朴实无华的结构，不过度架构。能跑就行

Assets/Scripts/NBC/Asset/Runtime/Tasks/Initialization/StepTasks/CheckUnpackPackageTask.cs

@@ -0,0 +1,38 @@
+using System.IO;
+
+namespace NBC.Asset
+{
+    /// <summary>
+    /// 检查是否需要解压package清单文件
+    /// </summary>
+    public class CheckUnpackPackageTask : NTask
+    {
+        private readonly ParallelTaskCollection _taskList = new ParallelTaskCollection();
+        private readonly bool _download;
+
+        public CheckUnpackPackageTask(bool download = false)
+        {
+            _download = download;
+        }
+
+        protected override void OnStart()
+        {
+            var versionData = Util.ReadJson<VersionData>(Const.GetCachePath(Const.VersionFileName));
+            if (versionData != null)
+            {
+                var cachePath = Const.GetCachePath(versionData.NameHash);
+                if (!File.Exists(cachePath))
+                {
+                    _taskList.AddTask(new UnpackFileTask(versionData.NameHash, _download));
+                }
+            }
+
+            _taskList.Run(TaskRunner.Def);
+        }
+
+        protected override NTaskStatus OnProcess()
+        {
+            return _taskList.IsDone ? _taskList.Status : NTaskStatus.Running;
+        }
+    }
+}