feat(game): add setClientGameStageConnected method to manage client state transitions

src/game/GameState.cpp

@@ -154,6 +154,11 @@ namespace UNO::GAME {
         return this->player_.isEmpty();
     }
 
+    void ClientGameState::setClientGameStageConnected()
+    {
+        this->clientGameStage_ = ClientGameStage::PRE_GAME;
+    }
+
     ClientGameStage ClientGameState::getClientGameStage() const
     {
         return this->clientGameStage_;

src/game/GameState.h

@@ -362,6 +362,11 @@ namespace UNO::GAME {
          */
         [[nodiscard]] ClientGameStage getClientGameStage() const;
 
+        /**
+         * 将客户端状态设置为已连接
+         */
+        void setClientGameStageConnected();
+
         /**
          * 结束当前局
          */