Fix: Issue 978 - Missing @summary annotation (#979)

Fixes https://github.com/shoelace-style/shoelace/issues/978

scripts/plop/templates/component/component.hbs

@@ -7,6 +7,8 @@ import styles from './{{ tagWithoutPrefix tag }}.styles';
 import type { CSSResultGroup } from 'lit';
 
 /**
+ * @summary Short summary of the component's intended use.
+ * 
  * @since 2.0
  * @status experimental
  *