fix(账号管理): 调度批量结果明细与刷新优化

补充批量调度返回 success_ids/failed_ids 并增加合约/单测

前端加入降级处理与部分失败提示，表格行使用稳定 key

测试: make test-frontend

测试: go test ./internal/service -run BulkUpdateAccounts -tags=unit

测试: go test ./internal/server -run APIContracts -tags=unit

frontend/src/components/common/README.md

@@ -13,6 +13,7 @@ A generic data table component with sorting, loading states, and custom cell ren
 - `columns: Column[]` - Array of column definitions with key, label, sortable, and formatter
 - `data: any[]` - Array of data objects to display
 - `loading?: boolean` - Show loading skeleton
+- `rowKey?: string | (row: any) => string | number` - Row key field or resolver (defaults to `row.id`, falls back to index)
 
 **Slots:**