Use bio's first sentence as homepage meta description

[Copilot]

Homepage meta description was generic tagline ("Technology leadership, collaboration, and open source"). Now uses bio's first sentence for better SEO specificity.

Changes

• src/content/about-bio.ts: Added getFirstSentence() to extract and strip markdown from first sentence
• src/pages/index.astro: Replaced siteConfig.description with getFirstSentence(aboutContent)
• src/content/about-bio.test.ts: Tests for sentence extraction and markdown stripping

Result

<!-- Before -->
<meta name="description" content="Technology leadership, collaboration, and open source">

<!-- After -->
<meta name="description" content="Ben Balter is the Director of Hubber Enablement within the Office of the COO at GitHub, the world's largest software development platform, ensuring all Hubbers can do their best (remote) work.">

First 150 chars contain job title, company, and role - optimized for search snippet display.

Original prompt

---

This section details on the original issue you should resolve

<issue_title>Meta description on index should be first sentence of bio</issue_title>
<issue_description></issue_description>

Comments on the Issue (you are @copilot in this section)

Custom agent used: seo
Specialized agent for SEO optimization including meta tags, structured data, page titles, descriptions, URL structure, and search engine visibility

• Fixes Meta description on index should be first sentence of bio #1626

---

💬 We'd love your input! Share your thoughts on Copilot coding agent in our 2 minute survey.