Incorrect (monolithic component):

// app/components/user-card.gjs
import Component from '@glimmer/component';

class UserCard extends Component {
  <template>
    <div class="user-card">
      <div class="header">
        <img src={{@user.avatar}} alt={{@user.name}} />
        <h3>{{@user.name}}</h3>
        <p>{{@user.email}}</p>
      </div>

      {{#if @showActions}}
        <div class="actions">
          <button {{on "click" @onEdit}}>Edit</button>
          <button {{on "click" @onDelete}}>Delete</button>
        </div>
      {{/if}}

      {{#if @showStats}}
        <div class="stats">
          <span>Posts: {{@user.postCount}}</span>
          <span>Followers: {{@user.followers}}</span>
        </div>
      {{/if}}
    </div>
  </template>
}