feat: support folder index pages

apps/server/internal/httpserver/static/site.css

@@ -160,13 +160,66 @@ code {
   text-decoration: none;
 }
 
+.browser-item-label {
+  display: inline-flex;
+  min-width: 0;
+  align-items: center;
+  gap: 0.45rem;
+}
+
+.browser-icon {
+  position: relative;
+  display: inline-block;
+  width: 1rem;
+  height: 0.9rem;
+  flex: 0 0 auto;
+}
+
+.browser-icon--folder {
+  margin-top: 0.1rem;
+  border: 1px solid rgba(15, 91, 216, 0.24);
+  border-radius: 0.18rem;
+  background: var(--accent-soft);
+}
+
+.browser-icon--folder::before {
+  position: absolute;
+  top: -0.22rem;
+  left: 0.1rem;
+  width: 0.45rem;
+  height: 0.25rem;
+  border: 1px solid rgba(15, 91, 216, 0.24);
+  border-bottom: 0;
+  border-radius: 0.14rem 0.14rem 0 0;
+  background: var(--accent-soft);
+  content: "";
+}
+
+.browser-icon--file {
+  border: 1px solid var(--border);
+  border-radius: 0.16rem;
+  background: rgba(255, 255, 255, 0.72);
+}
+
+.browser-icon--file::before {
+  position: absolute;
+  right: -1px;
+  top: -1px;
+  width: 0.3rem;
+  height: 0.3rem;
+  border-left: 1px solid var(--border);
+  border-bottom: 1px solid var(--border);
+  background: var(--panel);
+  content: "";
+}
+
 .miller-column a:hover,
 .miller-column a.is-active {
   background: var(--accent-soft);
   color: var(--accent);
 }
 
-.miller-column a span:first-child {
+.browser-item-label span:last-child {
   overflow: hidden;
   text-overflow: ellipsis;
   white-space: nowrap;