style: update theme tokens to white color scheme

- Update bgLayout to #f5f5f5 (light gray layout background)
- Update header colorBgHeader to #ffffff (white header background)
- Update header text colors to dark (#262626, #595959)
- Increase header height to 64px
- Add comprehensive sider color tokens for white menu theme
- Add selected menu item styling with blue highlight

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

src/common/libs/umi/layoutConfig.tsx

@@ -47,15 +47,19 @@ export const LayoutConfig: RuntimeConfig['layout'] = () => {
     // },
     collapsedButtonRender: false,
     token: {
-      bgLayout: '#eef0f3',
+      bgLayout: '#f5f5f5', // 浅灰布局背景
       header: {
-        colorBgHeader: '#001529',
-        colorHeaderTitle: '#FFF',
-        colorTextRightActionsItem: '#FFF',
-        heightLayoutHeader: 50,
+        colorBgHeader: '#ffffff', // 白色header背景
+        colorHeaderTitle: '#262626', // 深色标题文字
+        colorTextRightActionsItem: '#595959', // 深色操作文字
+        heightLayoutHeader: 64, // Header高度64px
       },
       sider: {
-        colorMenuBackground: '#FFF',
+        colorMenuBackground: '#ffffff', // 白色菜单背景
+        colorMenuText: '#595959', // 深色菜单文字
+        colorMenuTextSelected: '#1890ff', // 激活菜单文字蓝色
+        colorMenuItemBgSelected: '#e6f7ff', // 激活菜单背景浅蓝
+        colorMenuDivider: '#f0f0f0', // 分割线颜色
       },
     },
     menuItemRender: (item, dom) => <Link to={item.path || '/'}>{dom}</Link>,