优化结构

internal/data/README.md

@@ -1,7 +1,8 @@
 # Data Layer
 
-`data` owns database clients, persistence models, migrations, configuration
-watching, and repository implementations.
+`data` owns database clients, persistence models, migrations, explicit runtime
+configuration reloads, and repository implementations. File watching and
+immutable configuration snapshots belong to `internal/config`.
 
 - `system/`: system repositories and system table persistence
 - `task/`: timed-task tables and task persistence
@@ -28,5 +29,5 @@ reload locks. Do not split them into packages only to reduce file count.
 - `payment` 只拥有 `pay_orders` 等支付持久化，通过 `biz/integration.PaymentConfigReader`
   读取支付配置，不感知 integration 的 PO 或表结构。
 
-配置文件迁移、数据库切换、Redis/Mongo/对象存储重载仍属于根 data 的生命周期编排，
+配置文件持久化、数据库切换、Redis/Mongo/对象存储重载仍属于根 data 的生命周期编排，
 不等同于某个业务模块的表仓储。