refactor(client): 裸色字面量 F0F6FF/F0F4FF 迁移到 token

入库选填区/退单提示条 F0F6FF → infoSoft；表格列头 F0F4FF → thBg；
登录历史项/外壳用户菜单 hover → rowHover、菜单文字 → text。
深色主题 B / 暖色主题 C 下这些 chrome 现可正确随主题换色。

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01TSKEiHsvauyxYUW2itzUXX

client/lib/screens/inventory/inventory_check_screen.dart

@@ -353,8 +353,8 @@ class _InventoryCheckScreenState extends ConsumerState<InventoryCheckScreen> {
                               },
                               children: [
                                 TableRow(
-                                  decoration: const BoxDecoration(
-                                      color: Color(0xFFF0F4FF)),
+                                  decoration: BoxDecoration(
+                                      color: context.tokens.thBg),
                                   children: [
                                     '序号',
                                     '商品编码',