feat(message): 添加公告创建时间字段并修复未读消息计数逻辑

- 在 AdminNoticeVo 中添加 createTime 字段，用于显示公告创建时间
- 在 UserNoticeMapper.xml 中添加 createTime 的 MyBatis映射
- 修复 UserNoticeServiceImpl 中 countUnread 方法的逻辑错误，改为正确计算未读消息数量

src/main/java/com/zsc/edu/gateway/modules/message/service/impl/UserNoticeServiceImpl.java

@@ -86,7 +86,7 @@ public class UserNoticeServiceImpl extends ServiceImpl<UserNoticeRepository, Use
     public Integer countUnread(UserDetailsImpl userDetails) {
         LambdaQueryWrapper<UserNotice> lambdaQueryWrapper = new LambdaQueryWrapper<>();
         lambdaQueryWrapper.eq(UserNotice::getUserId, userDetails.getId())
-                .eq(UserNotice::getIsRead, true);
+                .eq(UserNotice::getIsRead, false);
         return Math.toIntExact(baseMapper.selectCount(lambdaQueryWrapper));
     }
 

src/main/java/com/zsc/edu/gateway/modules/message/vo/AdminNoticeVo.java

@@ -3,6 +3,8 @@ package com.zsc.edu.gateway.modules.message.vo;
 import com.zsc.edu.gateway.modules.message.entity.NoticeType;
 import lombok.Data;
 
+import java.time.LocalDateTime;
+
 /**
  * @author zhuang
  */
@@ -48,6 +50,10 @@ public class AdminNoticeVo {
      * 内容
      */
     public String content;
+    /**
+     * 创建时间
+     */
+    public LocalDateTime createTime;
     /**
      * 备注
      */

src/main/resources/mappers/notice/UserNoticeMapper.xml

@@ -33,6 +33,7 @@
         <result column="content" jdbcType="VARCHAR" property="content"/>
         <result column="remark" jdbcType="VARCHAR" property="remark"/>
         <result column="user_count" jdbcType="INTEGER" property="userCount"/>
+        <result column="create_time" jdbcType="DATE" property="createTime"/>
         <result column="read_count" jdbcType="INTEGER" property="readCount"/>
     </resultMap>
     <select id="selectByNoticeIdAndUserId" resultType="com.zsc.edu.gateway.modules.message.vo.UserNoticeVo"