```txtfeat(user): 实现用户充值功能

新增一个用户充值功能，用户可以通过POST请求向其账户内余额进行充值。
在SysUserController中添加了addUserMoney接口，通过调用UserService中的addUserMoney服务来实现。
同时，更新了SysUserMapper及SysUserMapper.xml以支持数据库中用户余额的增加。
```

src/main/java/com/muyu/system/controller/SysUserController.java

@@ -283,6 +283,13 @@ public class SysUserController extends BaseController {
     }
 
 
+    //TODO
+    @PostMapping("/addUserMoney")
+    public Result<String> addUserMoney(@RequestBody SysUser user){
+        return Result.success(userService.addUserMoney(user));
+    }
+
+
 
 
     /**

src/main/java/com/muyu/system/mapper/SysUserMapper.java

@@ -147,4 +147,8 @@ public interface SysUserMapper extends BaseMapper<SysUser> {
 
 
     BigDecimal selectBalance(Long userId);
+
+
+    int addUserMoney(SysUser user);
+
 }

src/main/java/com/muyu/system/service/SysUserService.java

@@ -231,4 +231,8 @@ public interface SysUserService extends IService<SysUser> {
 
 
     BigDecimal selectBalance(Long userId);
+
+
+    String addUserMoney(SysUser user);
+
 }

src/main/java/com/muyu/system/service/impl/SysUserServiceImpl.java

@@ -132,6 +132,15 @@ public class SysUserServiceImpl extends ServiceImpl<SysUserMapper, SysUser> impl
         return userMapper.selectBalance(userId);
     }
 
+    @Override
+    public String addUserMoney(SysUser user) {
+        int i = userMapper.addUserMoney(user);
+        if(i <= 0){
+            throw new RuntimeException("充值失败");
+        }
+        return "充值成功";
+    }
+
     /**
      * 查询用户所属角色组
      *

src/main/resources/mapper/system/SysUserMapper.xml

@@ -184,10 +184,16 @@
           and del_flag = '0'
         limit 1
     </select>
+
     <select id="selectBalance" resultType="java.math.BigDecimal">
            select user_balance from sys_user where user_id = #{userId}
     </select>
 
+
+    <update id="addUserMoney">
+        update sys_user set user_balance = user_balance + #{userBalance} where user_id = #{userId}
+    </update>
+
     <insert id="insertUser" parameterType="com.muyu.common.system.domain.SysUser" useGeneratedKeys="true" keyProperty="userId">
         insert into sys_user(
         <if test="userId != null and userId != 0">user_id,</if>