feat(client): 库存移动卡片品名后缀生产日期 + 商品抽屉生产日期行

- 原型先行（L1）：mobile-atoms 新增 .mc-nm .mc-date 原子（xs muted mono 左距8），
  index.html 登记，m-inventory 卡片模板与详情 sheet 同步补生产日期
- MCard 新增 nmSuffix 插槽镜像 .mc-date；库存窄屏卡片品名后缀生产日期小字
- Product 模型补 production_date（只读侧，不进 toJson）；商品抽屉信息区
  新增「生产日期」行（分类后、当前库存前，mono）
- 重生成库存移动 golden ×6（inventory_list_mobile / m_inventory 三主题）

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

client/lib/models/product.dart

@@ -14,6 +14,8 @@ class Product {
   final double? purchasePrice;
   final double? salePrice;
   final int? minStock;
+  // 生产日期（YYYY-MM-DD，后端 Date 序列化，空串=未填）
+  final String? productionDate;
   final String? description;
   final String? remark;
   final Map<String, dynamic>? customFields;
@@ -41,6 +43,7 @@ class Product {
     this.purchasePrice,
     this.salePrice,
     this.minStock,
+    this.productionDate,
     this.description,
     this.remark,
     this.customFields,
@@ -75,6 +78,7 @@ class Product {
         minStock: json['min_stock'] != null
             ? (json['min_stock'] as num).toInt()
             : null,
+        productionDate: json['production_date'] as String?,
         description: json['description'] as String?,
         remark: json['remark'] as String?,
         customFields: json['custom_fields'] as Map<String, dynamic>?,

client/lib/screens/inventory/inventory_list_screen.dart

@@ -613,6 +613,8 @@ class _InventoryListScreenState extends ConsumerState<InventoryListScreen> {
     return MCard(
       onTap: item.productId != null ? () => _openEditor(item) : null,
       nm: item.productName.isEmpty ? '-' : item.productName,
+      // 生产日期小字缀在品名后（原型 .mc-date，2026-07-10 用户口径）
+      nmSuffix: (item.productionDate ?? '').isEmpty ? null : item.productionDate,
       sub: sub.isEmpty ? null : sub,
       badges: [DsTextIconBadge(status)],
       amtWidget: Text.rich(

client/lib/widgets/ds/m_card.dart

@@ -101,6 +101,9 @@ class MCard extends StatelessWidget {
   /// mc-nm 标题（600 heading）。
   final String nm;
 
+  /// mc-date 标题后缀（原型 .mc-nm .mc-date：xs muted mono，左距 8）；null 不渲染。
+  final String? nmSuffix;
+
   /// mc-sub 副行（xs muted mono）；null 不渲染。
   final String? sub;
 
@@ -119,6 +122,7 @@ class MCard extends StatelessWidget {
   const MCard({
     super.key,
     required this.nm,
+    this.nmSuffix,
     this.sub,
     this.badges = const [],
     this.amt,
@@ -151,13 +155,32 @@ class MCard extends StatelessWidget {
                     child: Column(
                       crossAxisAlignment: CrossAxisAlignment.start,
                       children: [
-                        Text(nm,
-                            maxLines: 1,
-                            overflow: TextOverflow.ellipsis,
-                            style: TextStyle(
-                                fontSize: AppDims.fsBody,
-                                fontWeight: FontWeight.w600,
-                                color: t.heading)),
+                        Row(
+                          mainAxisSize: MainAxisSize.min,
+                          crossAxisAlignment: CrossAxisAlignment.baseline,
+                          textBaseline: TextBaseline.alphabetic,
+                          children: [
+                            Flexible(
+                              child: Text(nm,
+                                  maxLines: 1,
+                                  overflow: TextOverflow.ellipsis,
+                                  style: TextStyle(
+                                      fontSize: AppDims.fsBody,
+                                      fontWeight: FontWeight.w600,
+                                      color: t.heading)),
+                            ),
+                            if (nmSuffix != null) ...[
+                              const SizedBox(width: 8),
+                              Text(nmSuffix!,
+                                  style: TextStyle(
+                                      fontSize: AppDims.fsXs,
+                                      color: t.muted,
+                                      fontFamily: AppFonts.mono,
+                                      fontFamilyFallback:
+                                          AppFonts.monoFallback)),
+                            ],
+                          ],
+                        ),
                         if (sub != null) ...[
                           const SizedBox(height: 3),
                           Text(sub!,

client/lib/widgets/product_editor_drawer.dart

@@ -394,6 +394,9 @@ class _ProductEditorDrawerState extends ConsumerState<_ProductEditorDrawer> {
     if ((p.series ?? '').isNotEmpty) rows.add(('系列', b(p.series!)));
     if ((p.spec ?? '').isNotEmpty) rows.add(('规格', b(p.spec!)));
     if ((p.categoryName ?? '').isNotEmpty) rows.add(('分类', b(p.categoryName!)));
+    if ((p.productionDate ?? '').isNotEmpty) {
+      rows.add(('生产日期', b(p.productionDate!, mono: true)));
+    }
     if (widget.qty != null) {
       rows.add((
         '当前库存',