deploy(single-stack): 单栈收敛——v2 并入 deploy compose，v1 退役

- docker-compose.yml 重写为单栈 4 容器（admin 边缘 + v2-api/v2-admin/v2-postgres），
  v2 数据卷 deploy-v2_pgdata/uploads 以 external 引用，数据零迁移
- nginx：/uploads/ /assets/ 上游改 v2-api（product-center 覆盖块随之冗余移除），
  / 跳转 /v2/admin/；docker-compose.v2.yml 删除（血统已并入 develop）
- v1 api+postgres 已停用未删，终档/快照/回滚手册见 deploy/backups/consolidation-*/
- 切换验证：v2 库切换前后行数完全一致；/v2-api /public /v2/admin /v2/h5
  /assets 全路由冒烟 + 公网端到端通过

deploy/nginx/admin.conf

@@ -88,25 +88,18 @@ server {
 
     # Uploaded files served by the API
     location /uploads/ {
-        proxy_pass http://api:3001/uploads/;
+        proxy_pass http://v2-api:3001/uploads/;
         proxy_set_header Host $host;
     }
 
     # Static product assets served by the API
     location /assets/ {
-        proxy_pass http://api:3001/assets/;
-        proxy_set_header Host $host;
-    }
-
-    # Product-center icons maintained in the v2 repo — serve from the v2 api
-    # (more specific prefix than /assets/, so it takes precedence)
-    location /assets/product-center/ {
-        proxy_pass http://v2-api:3001/assets/product-center/;
+        proxy_pass http://v2-api:3001/assets/;
         proxy_set_header Host $host;
     }
 
     # Website placeholder until the public site is deployed
     location / {
-        return 302 /admin/;
+        return 302 /v2/admin/;
     }
 }