feat: add permission-based access control and improve alert table UI

- Implement PermissionGuard component for route-level permission enforcement
- Add tree-based permission checkbox group in role management popup
- Gate SSE connection, unread count fetch, and rule edit actions on user permissions
- Add skip401Refresh option and auto token refresh on 401 response
- Improve alert table with fixed columns, explicit widths, and text ellipsis
- Add i18n entries for permission guide and rule menu descriptions (en/zh)
- Add expo-api nginx proxy configuration
- Add .claude to .gitignore

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

src/locales/zh_CN/pages.ts

@@ -321,6 +321,8 @@ export default {
   'form.role.placeholder2': '系统角色权限级别不可修改',
   'form.role.badgeColor': '徽章颜色',
   'form.role.menuIds': '绑定权限（菜单）',
+  'form.role.permissionGuide': '权限怎么选',
+  'form.role.otherPermissions': '其他菜单权限',
 
   'form.config.timezone': '时区设置',
   'form.config.timezone.title': '默认时区',