Show preview images and link cards in Compose

frontend/src/styles.css

@@ -1255,6 +1255,74 @@ select {
   object-fit: contain;
 }
 
+.link-preview-card {
+  display: flex;
+  gap: 12px;
+  margin-top: 12px;
+  padding: 10px;
+  border: 1px solid var(--border);
+  border-radius: 12px;
+  background: var(--surface);
+  text-decoration: none;
+  color: inherit;
+  overflow: hidden;
+}
+
+.link-preview-card.is-loading {
+  align-items: center;
+  padding: 14px;
+}
+
+.link-preview-image {
+  width: 112px;
+  height: 112px;
+  object-fit: cover;
+  border-radius: 8px;
+  flex-shrink: 0;
+}
+
+.link-preview-content {
+  display: flex;
+  flex-direction: column;
+  gap: 3px;
+  min-width: 0;
+}
+
+.link-preview-site {
+  font-size: 12px;
+  font-weight: 600;
+  text-transform: uppercase;
+  letter-spacing: 0.04em;
+  color: var(--text-muted);
+}
+
+.link-preview-title {
+  font-weight: 600;
+  line-height: 1.35;
+  overflow: hidden;
+  display: -webkit-box;
+  -webkit-line-clamp: 2;
+  -webkit-box-orient: vertical;
+}
+
+.link-preview-description {
+  font-size: 13px;
+  color: var(--text-muted);
+  line-height: 1.4;
+  overflow: hidden;
+  display: -webkit-box;
+  -webkit-line-clamp: 2;
+  -webkit-box-orient: vertical;
+}
+
+.link-preview-url {
+  font-size: 12px;
+  color: var(--text-muted);
+  overflow: hidden;
+  text-overflow: ellipsis;
+  white-space: nowrap;
+}
+
 /* -------------------------------------------------------------------------
    Relays
    ------------------------------------------------------------------------- */