feat: 添加 WebSocket 消息 DTO

src/main/java/com/webgame/webgamebackend/ws/dto/WsInboundMessage.java

@@ -0,0 +1,26 @@
+package com.webgame.webgamebackend.ws.dto;
+
+/**
+ * 客户端→服务端 WebSocket 消息类型
+ */
+public final class WsInboundMessage {
+
+    private WsInboundMessage() {}
+
+    /** 落子 */
+    public static final String PLACE_STONE = "place_stone";
+    /** 发送聊天 */
+    public static final String CHAT = "chat";
+    /** 准备/取消准备 */
+    public static final String READY = "ready";
+    /** 认输 */
+    public static final String RESIGN = "resign";
+    /** 求和请求 */
+    public static final String DRAW_REQUEST = "draw_request";
+    /** 同意/拒绝求和 */
+    public static final String DRAW_RESPONSE = "draw_response";
+    /** 离开房间 */
+    public static final String LEAVE = "leave";
+    /** 开始游戏（仅房主） */
+    public static final String START = "start";
+}

src/main/java/com/webgame/webgamebackend/ws/dto/WsMessage.java

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+package com.webgame.webgamebackend.ws.dto;
+
+/**
+ * WebSocket 消息通用封装
+ *
+ * @param type 消息类型
+ * @param data 消息数据（JSON 对象或基本类型）
+ */
+public record WsMessage(
+        String type,
+        Object data
+) {}

src/main/java/com/webgame/webgamebackend/ws/dto/WsOutboundMessage.java

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+package com.webgame.webgamebackend.ws.dto;
+
+/**
+ * 服务端→客户端 WebSocket 消息类型
+ */
+public final class WsOutboundMessage {
+
+    private WsOutboundMessage() {}
+
+    /** 棋盘全量同步 */
+    public static final String BOARD_SYNC = "board_sync";
+    /** 单步落子通知 */
+    public static final String MOVE = "move";
+    /** 轮次切换 */
+    public static final String TURN_CHANGE = "turn_change";
+    /** 聊天广播 */
+    public static final String CHAT_BROADCAST = "chat_broadcast";
+    /** 对局结束 */
+    public static final String GAME_OVER = "game_over";
+    /** 玩家加入 */
+    public static final String PLAYER_JOIN = "player_join";
+    /** 玩家离开 */
+    public static final String PLAYER_LEAVE = "player_leave";
+    /** 玩家准备状态变更 */
+    public static final String READY_CHANGE = "ready_change";
+    /** 观战者加入 */
+    public static final String SPECTATOR_JOIN = "spectator_join";
+    /** 观战者离开 */
+    public static final String SPECTATOR_LEAVE = "spectator_leave";
+    /** 走棋记录同步 */
+    public static final String MOVE_HISTORY = "move_history";
+    /** 错误消息 */
+    public static final String ERROR = "error";
+}