Group a limited number of featured posts in Siteleaf using Liquid.

featured.html

{% assign featured_ids = '' %}

Featured:
{% for post in taxonomy['tags']['featured'].posts limit:4 %}
{% assign featured_ids = featured_ids | append:',' | append:post.id %}
<li>{{post.title}}</li>
{% endfor %}

Everything else:
{% for post in posts %}
{% unless featured_ids contains post.id %}
<li>{{post.title}}</li>
{% endunless %}
{% endfor %}