feat(upserver): 保存M2客户端KV迁移至本人统计写检查点

保存独立KV用户服务、固定会话存档与原业务接线，以及C3d资料缓存和C3e本人统计写。
保留原PF/AGG路线、业务公式和时序；榜单读取、好友资料、公告、匹配及首场景闸仍待完成。

验证：ServiceHost两条件各33组646断言；Unity CLI Loop编译0错误269警告。
包含相关方案、评审裁决、测试及状态文档。未操作服务器、正式账号或打包。

Client/Assets/Scripts/TimeManager/TimeRefreshManager.cs

@@ -20,7 +20,7 @@ namespace TimeManager
 
             _sessionStartTime = ZZTimeHelper.UtcNow().UtcNowOffset();
             _lastCheckedHour = _sessionStartTime.Hour;
-            CheckLastLogin();
+            InitialRefreshSucceeded = CheckLastLogin();
             _tickService.MinuteTick
                 .Subscribe(_ =>
                 {
@@ -32,6 +32,7 @@ namespace TimeManager
 
         private readonly ITimeTickService _tickService;
         private readonly IUserService _userService;
+        public bool InitialRefreshSucceeded { get; }
 
         private int _lastCheckedDayOfYear = -1;
         private int _lastCheckedHour = -1;
@@ -40,11 +41,11 @@ namespace TimeManager
 
         #region Check登录时间
         
-        private void CheckLastLogin()
+        private bool CheckLastLogin()
         {
-            if (IsLastLoginToday()) return;
+            if (IsLastLoginToday()) return true;
             Debug.Log("上次登录不是今天");
-            OnCrossDayRefresh();
+            return OnCrossDayRefresh();
         }
         private void CheckSessionCrossDay()
         {
@@ -105,7 +106,8 @@ namespace TimeManager
         /// </summary>
         public DateTime? GetLastLoginTime()
         {
-            return _userService?.LastLoginTime;
+            var value = _userService?.LastLoginTime;
+            return value == DateTime.MinValue ? null : value;
         }
 
         /// <summary>
@@ -121,16 +123,18 @@ namespace TimeManager
         /// <summary>
         /// 跨天刷新逻辑
         /// </summary>
-        private void OnCrossDayRefresh()
+        private bool OnCrossDayRefresh()
         {
             try
             {
                 // 1. 发送活动跨天刷新事件
                 GContext.Publish(new ActivityCrossDayRefreshEvent());
+                return true;
             }
             catch (Exception e)
             {
                 Debug.LogError($"[TimeRefreshManager] Error during cross day refresh: {e.Message}\n{e.StackTrace}");
+                return false;
             }
         }