feat: 분류 순서변경(reorder) + 월 예상 수입 설정 API

- 분류: sort_order reorder 엔드포인트, 생성 시 맨 뒤 배치
- 예산: account_setting 테이블 + 월 예상 수입 GET/PUT

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

src/main/resources/db/account.sql

@@ -123,6 +123,14 @@ CREATE TABLE IF NOT EXISTS account_entry_tag (
     KEY idx_aet_tag (tag_id)
 ) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_unicode_ci;
 
+-- 사용자별 가계부 설정 (예: 월 예상 수입)
+CREATE TABLE IF NOT EXISTS account_setting (
+    member_id       BIGINT   NOT NULL COMMENT '소유자 member.id',
+    expected_income BIGINT   NULL COMMENT '월 예상 수입',
+    updated_at      DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP,
+    PRIMARY KEY (member_id)
+) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_unicode_ci;
+
 -- 투자 보유 종목 (INVEST 지갑별 · 사용자별)
 CREATE TABLE IF NOT EXISTS invest_holding (
     id            BIGINT      NOT NULL AUTO_INCREMENT,

src/main/resources/mapper/AccountSettingMapper.xml

@@ -0,0 +1,16 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE mapper PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN"
+        "https://mybatis.org/dtd/mybatis-3-mapper.dtd">
+<mapper namespace="com.sb.web.account.mapper.AccountSettingMapper">
+
+    <select id="findExpectedIncome" resultType="java.lang.Long">
+        SELECT expected_income FROM account_setting WHERE member_id = #{memberId}
+    </select>
+
+    <update id="upsertExpectedIncome">
+        INSERT INTO account_setting (member_id, expected_income, updated_at)
+        VALUES (#{memberId}, #{expectedIncome}, NOW())
+        ON DUPLICATE KEY UPDATE expected_income = #{expectedIncome}, updated_at = NOW()
+    </update>
+
+</mapper>

src/main/resources/mapper/CategoryMapper.xml

@@ -51,4 +51,14 @@
         DELETE FROM account_category WHERE id = #{id} AND member_id = #{memberId}
     </delete>
 
+    <update id="updateSortOrder">
+        UPDATE account_category SET sort_order = #{sortOrder}
+        WHERE id = #{id} AND member_id = #{memberId}
+    </update>
+
+    <select id="maxSortOrder" resultType="java.lang.Integer">
+        SELECT MAX(sort_order) FROM account_category
+        WHERE member_id = #{memberId} AND type = #{type}
+    </select>
+
 </mapper>