feat(MCA): TASK-003 数据库 Schema 变更 [AC-MCA-11]

- Session 表新增 channel_type 字段

- 默认值为 wechat

- 创建迁移脚本 V1__add_channel_type.sql

src/main/resources/db/init.sql

@@ -8,6 +8,7 @@ CREATE TABLE IF NOT EXISTS `session` (
     `session_id` VARCHAR(128) NOT NULL COMMENT '会话ID',
     `customer_id` VARCHAR(64) NOT NULL COMMENT '客户ID (external_userid)',
     `kf_id` VARCHAR(64) NOT NULL COMMENT '客服账号ID (open_kfid)',
+    `channel_type` VARCHAR(20) NOT NULL DEFAULT 'wechat' COMMENT '渠道类型: wechat/douyin/jd',
     `status` VARCHAR(20) NOT NULL DEFAULT 'AI' COMMENT '状态: AI/PENDING/MANUAL/CLOSED',
     `wx_service_state` INT DEFAULT 0 COMMENT '微信会话状态: 0-未处理/1-智能助手/2-待接入池/3-人工接待/4-已结束',
     `created_at` DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP COMMENT '创建时间',
@@ -18,6 +19,7 @@ CREATE TABLE IF NOT EXISTS `session` (
     INDEX `idx_customer_id` (`customer_id`),
     INDEX `idx_kf_id` (`kf_id`),
     INDEX `idx_status` (`status`),
+    INDEX `idx_channel_type` (`channel_type`),
     INDEX `idx_updated_at` (`updated_at`)
 ) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_unicode_ci COMMENT='会话表';
 
@@ -75,3 +77,4 @@ CREATE TABLE IF NOT EXISTS `quick_reply` (
 
 -- 如果表已存在，添加新字段
 ALTER TABLE `session` ADD COLUMN IF NOT EXISTS `wx_service_state` INT DEFAULT 0 COMMENT '微信会话状态';
+ALTER TABLE `session` ADD COLUMN IF NOT EXISTS `channel_type` VARCHAR(20) DEFAULT 'wechat' COMMENT '渠道类型: wechat/douyin/jd';

src/main/resources/db/migration/V1__add_channel_type.sql

@@ -0,0 +1,10 @@
+-- TASK-003: 数据库 Schema 变更 [AC-MCA-11]
+-- Session 表新增 channel_type 字段
+
+ALTER TABLE `session` 
+ADD COLUMN IF NOT EXISTS `channel_type` VARCHAR(20) DEFAULT 'wechat' 
+COMMENT '渠道类型: wechat/douyin/jd' 
+AFTER `kf_id`;
+
+-- 添加索引
+CREATE INDEX IF NOT EXISTS `idx_channel_type` ON `session` (`channel_type`);