feat(deploy): 完成数据迁移与MySQL全链路(14表698k消息100%一致+5方言补丁+bind mount)

- migrate_sqlite_to_mysql.py: 逐表清空重导(幂等),复用repos强转,JSON列
  解析,67万消息按msg_id键集分批,467s跑完14表全一致
- 修4个MySQL实测bug: NULLS LAST语法(compat.py编译补丁)、message.text
  TEXT→MEDIUMTEXT(64KB字节上限,实测20.8万字符车源清单)、URL列
  String(1024)→Text(分享链接超1KB)、垃圾超长member_id源头清理
- compose: media改bind mount(不占C盘Docker虚拟磁盘,实测2.5GB卷把
  C盘撑爆引擎500);mysql不映射宿主机3306
- 前端Dockerfile: npm ci→install(本地/容器npm版本锁漂移)
- 五服务实测:nginx→backend→MySQL全链路返回真实数据(客户6859/A**杰25条
  /搜索56条),媒体49536文件bind mount直读

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

docker-compose.yml

@@ -98,8 +98,9 @@ services:
       API_TOKEN: ${API_TOKEN:-}
       ENCRYPTION_KEY: ${ENCRYPTION_KEY:-}
     volumes:
-      # Persist downloaded media blobs across container restarts.
-      - media_data:/data/media
+      # 媒体走 bind mount(不占 Docker 虚拟磁盘——本机实测 C 盘被 2.5GB
+      # volume 撑爆导致引擎 500,2026-08-22);服务器上数据直观可见好备份
+      - ./yunke-server/media:/data/media
     ports:
       - "8000:8000"
 
@@ -136,10 +137,7 @@ services:
       FULL_SYNC_HOUR: ${FULL_SYNC_HOUR:-2}
       MESSAGE_INTERVAL_HOURS: ${MESSAGE_INTERVAL_HOURS:-4}
     volumes:
-      # Share the media volume with backend so both services see the same
-      # downloaded blobs (read-only would be ideal but the scheduler is the
-      # writer; mounting read-write here is the simplest correct config).
-      - media_data:/data/media
+      - ./yunke-server/media:/data/media
 
   # ----------------------------------------------------------------------- #
   # Frontend — built + served by nginx
@@ -159,4 +157,3 @@ services:
 volumes:
   mysql_data:
   redis_data:
-  media_data: