feat(oa): 添加文章管理功能

- 新增文章管理相关的实体类、Mapper、Service、Controller- 实现文章的增删改查、分页查询、导出等功能
- 添加数据校验和逻辑删除支持

ruoyi-oa/src/main/resources/mapper/oa/OaArticleMapper.xml

@@ -0,0 +1,21 @@
+<?xml version="1.0" encoding="UTF-8" ?>
+<!DOCTYPE mapper
+        PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN"
+        "http://mybatis.org/dtd/mybatis-3-mapper.dtd">
+<mapper namespace="com.ruoyi.oa.mapper.OaArticleMapper">
+
+    <resultMap type="com.ruoyi.oa.domain.OaArticle" id="OaArticleResult">
+        <result property="articleId" column="article_id"/>
+        <result property="title" column="title"/>
+        <result property="content" column="content"/>
+        <result property="accessory" column="accessory"/>
+        <result property="remark" column="remark"/>
+        <result property="createTime" column="create_time"/>
+        <result property="createBy" column="create_by"/>
+        <result property="updateTime" column="update_time"/>
+        <result property="updateBy" column="update_by"/>
+        <result property="delFlag" column="del_flag"/>
+    </resultMap>
+
+
+</mapper>