fix: use Image component for post list featured images

Changed from plain <img> to <Image> component so locally
uploaded images display correctly on the posts list page.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

src/pages/posts/index.astro

@@ -1,6 +1,7 @@
 ---
 import { getEmDashCollection, getTermsForEntries } from "emdash";
 import Base from "../../layouts/Base.astro";
+import { Image } from "emdash/ui";
 import { getReadingTime } from "../../utils/reading-time";
 
 // Sort in the database rather than in JS — lets the DB use its index on
@@ -54,7 +55,7 @@ const formatDate = (date: Date) =>
 							<a href={`/posts/${post.id}`} class="post-link">
 								{post.data.featured_image && (
 									<div class="post-image">
-										<img src={post.data.featured_image.src} alt={post.data.featured_image.alt} />
+										<Image image={post.data.featured_image} />
 									</div>
 								)}
 								<div class="post-meta">