feat: 完成7项功能任务

后端：
- fix(backend): InventoryLog 增加 Product/Warehouse 关联，Logs 接口加 Preload 修复流水记录显示"-"
- feat(backend): 新增 /inventory/batches 批次追踪接口
- feat(backend): 新增财务记录、编号规则接口（finance、number_rule handler）
- fix(backend): service/stock_test.go 修复 model.Date 类型错误

前端：
- feat(client): 入库/出库管理 Tab 调换顺序（审核在前），审核 Tab 加新建按钮，列表 Tab 无按钮
- feat(client): 入库单/出库单增加详情弹窗，显示完整单据信息和商品明细
- feat(client): 完善出库单新建表单（StockOutFormScreen），支持选客户/仓库/商品
- fix(client): StockInItem/StockOutItem.fromJson 修复读取嵌套 product 对象而非平铺字段
- feat(client): 批次追踪页面（BatchTrackingScreen）及侧边栏入口
- feat(client): 财务管理、盘点、编号规则接入真实后端 API
- fix(client): 入库/出库审核通过后 invalidate inventoryListProvider 刷新库存

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

client/lib/core/router/app_router.dart

@@ -6,8 +6,10 @@ import '../../screens/shell/app_shell.dart';
 import '../../screens/stock_in/stock_in_list_screen.dart';
 import '../../screens/stock_in/stock_in_form_screen.dart';
 import '../../screens/stock_out/stock_out_list_screen.dart';
+import '../../screens/stock_out/stock_out_form_screen.dart';
 import '../../screens/inventory/inventory_list_screen.dart';
 import '../../screens/inventory/inventory_check_screen.dart';
+import '../../screens/inventory/batch_tracking_screen.dart';
 import '../../screens/partners/partners_screen.dart';
 import '../../screens/finance/finance_screen.dart';
 import '../../screens/products/products_screen.dart';
@@ -83,6 +85,9 @@ final appRouterProvider = Provider<GoRouter>((ref) {
           GoRoute(
               path: '/stock-out',
               pageBuilder: (_, __) => _noTransition(const StockOutListScreen())),
+          GoRoute(
+              path: '/stock-out/new',
+              pageBuilder: (_, __) => _noTransition(const StockOutFormScreen())),
           GoRoute(
               path: '/inventory',
               pageBuilder: (_, __) =>
@@ -91,6 +96,10 @@ final appRouterProvider = Provider<GoRouter>((ref) {
               path: '/inventory/check',
               pageBuilder: (_, __) =>
                   _noTransition(const InventoryCheckScreen())),
+          GoRoute(
+              path: '/batches',
+              pageBuilder: (_, __) =>
+                  _noTransition(const BatchTrackingScreen())),
           GoRoute(
               path: '/partners',
               pageBuilder: (_, __) => _noTransition(const PartnersScreen())),