feat: SO-ISMCTS 备选方案 (非默认)

SOIsmctsBot.cs (新文件, 284行):
- 单树共享统计: SONode 累积所有候选的胜/负
- 200次检查收敛: winRate>90% → 提前终止
- 整合 HandOptimizer/CardTracker/EndgameSolver/LockDetector

性能问题 (当前不启用):
- 每次模拟重新生成对手手牌(48张TCardInfoPdkF) → 5-8x慢
- 优化方向: 对象池缓存+批量determinization
- 作为备选bot保留, InitBots仍用 IsmctsBot

PdkFriendServer/Logic/PdkGameMain.cs

@@ -58,11 +58,11 @@ namespace PdkFriendServer.Logic
 
         /// <summary>懒初始化3个bot（BotMode==true时首次WaitWanJiaShuRu调用）</summary>
         private void InitBots()
-        {
-            _bots = new IPdkBot[3];
-            for (int i = 0; i < 3; i++)
-                _bots[i] = new IsmctsBot();
-        }
+                {
+                    _bots = new IPdkBot[3];
+                    for (int i = 0; i < 3; i++)
+                        _bots[i] = new IsmctsBot();
+                }
 
         /// <summary>构建当前玩家的可见视图——只看自己手牌+公开信息</summary>
         private PdkBotView BuildBotView(int pos)