resources/views/layouts/_header.blade.php中分类没有从数据库读取，导致最后网站设置修改分类时，头部分类不会改变，修改如下：

<ul class="nav navbar-nav">
    <li class="{{ active_class(if_route('topics.index')) }}"><a href="{{ route('topics.index') }}">话题</a></li>
    @foreach( \App\Models\Category::all() as $category )
        <li class="{{ active_class((if_route('categories.show') && if_route_param('category', $category->id))) }}"><a href="{{ route('categories.show', $category->id) }}">{{ $category->name }}</a></li>
    @endforeach
</ul>