fix(web): 本地优先保存与 design 页体验修复

- 保存先写本地缓存，登录后可选云端同步；退出登录不再因文件操作跳转登录

- 修复 Layui 遮罩残留、design2 保存后线条、toast 被 finally 提前关闭

- 保存过程恢复 loading spinner；成功提示 2.5 秒

- 云端 payload 瘦身与体积超限提示；后端 schema 迁移与 FileService 容错

Co-authored-by: Cursor <cursoragent@cursor.com>

frontend-web/config/local.js.example

@@ -1,8 +1,9 @@
-// 复制为同目录 local.js（全量更新 frontend 时不要覆盖 local.js）
-
-window.SOON_DEPLOY_CONFIG = {
-
-  api_v1_base: 'https://designadmin.cardsoon.com/api/v1',
-
-  api_admin_base: 'https://designadmin.cardsoon.com/api/admin',
-
+// 复制为同目录 local.js（全量更新 frontend 时不要覆盖 local.js）
+window.SOON_DEPLOY_CONFIG = {
+  api_v1_base: 'https://designadmin.cardsoon.com/api/v1',
+  api_admin_base: 'https://designadmin.cardsoon.com/api/admin',
+  front_base_url: 'https://design.cardsoon.com',
+  web_base: 'https://design.cardsoon.com',
+  version: '1.0.0'
+};
+