feat: add hero image for blog post on AI agent skills

Author: alexandramartinez

src/assets/blog/what-are-ai-agent-skills-and-how-to-use-them.png

@@ -4,6 +4,7 @@ description: "A beginner's guide to AI agent skills: what a SKILL.md file is, ho
 pubDate: 2026-07-04
 category: Guides
 tags: [AI, Claude Code, Markdown]
+heroImage: ../../assets/blog/what-are-ai-agent-skills-and-how-to-use-them.png
 faqs:
   - question: "What is an AI agent skill?"
     answer: "A skill is a Markdown file called SKILL.md inside a folder. It has a short YAML header with a `name` and a `description`, followed by the instructions themselves written in Markdown. It saves a piece of information or a workflow so you (or your AI) don't have to re-explain it every time."