feat(client): 登录/注册页照原型重建，ds 真相源组件族统一全部屏

- 登录/注册（login.html/register.html 1:1）：两栏卡片+品牌渐变面板+主题小衣服
  pill（onSurface 变体）+记住我（记录并预填最近账号）+原型式 toast 校验；
  登录 fidelity 1.4–2.1% 三主题全绿；注册暂不入闸（少 门店编号/兑换券 字段，
  已记 CONTRACT，screens.mjs 留存根）
- ds 原子补齐：DsToast（.toast 单例）/DsCheck（.check/.agree）/DsButton lg 档/
  DsSelect 替换全部旧 DropdownButton/DsField label 在上/DsInput 后缀与密码形态
- 全屏统一：对话框按钮全 DsButton、盒式输入主题钉死（visualDensity.standard、
  h38、InputDecorationTheme 渗漏修复）、图标全 lucide、JetBrains Mono 三端同源、
  BrandMark 真相源 logo、只读模式写操作全量守卫（WriteGuard+DsToast）
- 出入库列表：版式对齐原型（卡片对齐+搜索框居中）、KPI 近30天滚动、结清后
  失效财务应收应付表；商品编辑抽屉介绍库改搜索下拉、图片双击全屏预览
- 删除旧 UI 死代码：DataTableCard/FormDialog/PageScaffold/SearchChip/
  SelectProductDialog/tabStateProvider
- golden/fidelity：stock-in/out 补注册（9%）、login 入册（8%）、goldens 全量重打；
  修复 pubspec flutter_web_plugins 非法声明（CI pub get 阻断）

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

client/lib/repositories/product_repository.dart

@@ -113,12 +113,14 @@ class ProductRepository {
     try {
       final MultipartFile file;
       if (bytes != null) {
-        file = MultipartFile.fromBytes(bytes, filename: fileName ?? 'image.jpg');
+        file =
+            MultipartFile.fromBytes(bytes, filename: fileName ?? 'image.jpg');
       } else {
         file = await MultipartFile.fromFile(filePath!);
       }
       final formData = FormData.fromMap({'file': file});
-      final resp = await _client.post('/products/$productId/images', data: formData);
+      final resp =
+          await _client.post('/products/$productId/images', data: formData);
       return ProductImage.fromJson(
           (resp.data as Map<String, dynamic>)['data'] as Map<String, dynamic>);
     } on DioException catch (e) {
@@ -170,7 +172,8 @@ class ProductRepository {
       if (originId != null) body['origin_id'] = originId;
       if (shelfLifeId != null) body['shelf_life_id'] = shelfLifeId;
       if (storageId != null) body['storage_id'] = storageId;
-      if (descriptionDocId != null) body['description_doc_id'] = descriptionDocId;
+      if (descriptionDocId != null)
+        body['description_doc_id'] = descriptionDocId;
       final resp = await _client.post('/products/find-or-create', data: body);
       return Product.fromJson(
           (resp.data as Map<String, dynamic>)['data'] as Map<String, dynamic>);