feat(client): 出库明细成本/售价/利润三列重设计 + 建单利润列 + 入库列头统一

- 出库详情抽屉（管理员）：数量/成本价/售价/利润 + 合计金额/合计利润 双行；
  operator 见 售价/小计（服务端抹零+前端隐藏双保险）；利润负数 danger
- 出库建单：商品名称下带编码（字体同系列列）；金额列→利润列（实时）；
  底栏合计利润（仅管理员）；进价列仅管理员；提交发新 key（cost_price/sale_price）
- 入库建单列头：进价（单瓶）/ 参考售价 / 总进价
- 退单弹窗金额改售价口径（与冲应收一致）；打印保留待定价回退成本兼容
- models 字段随后端消歧改名；golden 重打；新增抽屉双形态 widget 测试

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01JJ1g8XV1YhhmHRzhwWEW7o

client/lib/models/stock_out.dart

@@ -3,9 +3,10 @@ class StockOutItem {
   final int? orderId;
   final int productId;
   final double quantity;
-  final double unitPrice;
-  final double salePrice;
-  final double totalPrice;
+  final double costPrice; // 成本单价（入库成本快照，仅管理员可见——operator 响应被服务端抹零）
+  final double salePrice; // 销售单价
+  final double costAmount; // 成本小计 = quantity × costPrice
+  final double saleAmount; // 售价小计 = quantity × salePrice（待定价=0）
   final double returnedQuantity;
   final String? productName;
   final String? productCode;
@@ -22,9 +23,10 @@ class StockOutItem {
     this.orderId,
     required this.productId,
     required this.quantity,
-    required this.unitPrice,
+    this.costPrice = 0,
     this.salePrice = 0,
-    required this.totalPrice,
+    this.costAmount = 0,
+    this.saleAmount = 0,
     this.returnedQuantity = 0,
     this.productName,
     this.productCode,
@@ -51,9 +53,10 @@ class StockOutItem {
           json['order_id'] != null ? (json['order_id'] as num).toInt() : null,
       productId: (json['product_id'] as num).toInt(),
       quantity: (json['quantity'] as num).toDouble(),
-      unitPrice: (json['unit_price'] as num).toDouble(),
+      costPrice: (json['cost_price'] as num?)?.toDouble() ?? 0,
       salePrice: (json['sale_price'] as num?)?.toDouble() ?? 0,
-      totalPrice: (json['total_price'] as num).toDouble(),
+      costAmount: (json['cost_amount'] as num?)?.toDouble() ?? 0,
+      saleAmount: (json['sale_amount'] as num?)?.toDouble() ?? 0,
       returnedQuantity: (json['returned_quantity'] as num?)?.toDouble() ?? 0,
       productName: lineOrProduct('product_name', 'name'),
       productCode: lineOrProduct('product_code', 'code'),
@@ -85,7 +88,8 @@ class StockOutOrder {
   final String? orderDate;
   final String? reviewedAt;
   final String? createdAt;
-  final double? totalAmount;
+  final double? saleTotal; // 应收合计 = Σ 售价小计
+  final double profitTotal; // 总利润（仅管理员可见，operator 被抹零）
   final String? remark;
   final List<StockOutItem> items;
 
@@ -106,7 +110,8 @@ class StockOutOrder {
     this.orderDate,
     this.reviewedAt,
     this.createdAt,
-    this.totalAmount,
+    this.saleTotal,
+    this.profitTotal = 0,
     this.remark,
     this.items = const [],
   });
@@ -138,9 +143,10 @@ class StockOutOrder {
         orderDate: json['order_date'] as String?,
         reviewedAt: json['reviewed_at'] as String?,
         createdAt: json['created_at'] as String?,
-        totalAmount: json['total_amount'] != null
-            ? (json['total_amount'] as num).toDouble()
+        saleTotal: json['sale_total'] != null
+            ? (json['sale_total'] as num).toDouble()
             : null,
+        profitTotal: (json['profit_total'] as num?)?.toDouble() ?? 0,
         remark: json['remark'] as String?,
         items: json['items'] != null
             ? (json['items'] as List)