feat: EpicScriptService 新增 switchVersion 方法声明

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

server/src/main/java/com/emotion/service/EpicScriptService.java

@@ -74,6 +74,15 @@ public interface EpicScriptService extends IService<EpicScript> {
      */
     EpicScriptResponse selectScript(String id);
 
+    /**
+     * 切换剧本当前生效版本
+     *
+     * @param scriptId 剧本ID
+     * @param messageId 消息ID
+     * @return 剧本响应
+     */
+    EpicScriptResponse switchVersion(String scriptId, String messageId);
+
     /**
      * 删除剧本
      *