feat: use astro:assets for social .svgs too

[JoshuaKGoldberg]

PR Checklist

• [x] Addresses an existing open issue: fixes #261
• [x] That issue was marked as status: accepting prs
• [x] Steps in CONTRIBUTING.md were taken

Overview

Refactors some stuff from Solid to Astro to make use of Astro's <Image />.

[vercel[bot]]

The latest updates on your projects. Learn more about Vercel for Git ↗︎

Name	Status	Preview	Comments	Updated (UTC)
joshuakgoldberg-dot-com	✅ Ready (Inspect)	Visit Preview	💬 Add feedback	Mar 12, 2024 7:01pm