feat: 优化后台文案

server/app/Admin/Controllers/ProductCategoryController.php

@@ -68,7 +68,7 @@ class ProductCategoryController extends AdminController
                 ->options(config('global.cat_level'))
                 ->default(1);
             $form->text('name')->required();
-            $form->image('cover_img','封面图（宽高比 1.4:1）')->saveFullUrl()
+            $form->image('cover_img','封面图（宽高比 1.75:1）')->saveFullUrl()
                 ->uniqueName()->autoUpload()
                 ->autoSave(false)
                 ->removable(false)

server/app/Admin/Controllers/ShowroomController.php

@@ -46,7 +46,7 @@ class ShowroomController extends AdminController
         return Form::make(new Showroom(), function (Form $form) {
             $form->display('id');
             $form->text('name')->required();
-            $form->image('cover_img','封面图（宽高比1.4:1）')->saveFullUrl()
+            $form->image('cover_img','封面图（宽高比1.75:1）')->saveFullUrl()
                 ->uniqueName()->autoUpload()
                 ->autoSave(false)
                 ->removable(false)