dynamic bar count (multiples of 28), header overflow fix, parentId index for faster chain lookups

wwwroot/style.css

@@ -30,8 +30,12 @@ header {
   align-items: center;
   gap: 24px;
   flex-shrink: 0;
+  overflow-x: auto;
+  flex-wrap: nowrap;
 }
 
+header > * { flex-shrink: 0; }
+
 header h1 { font-size: 1.1rem; font-weight: 600; color: var(--accent); }
 
 #anchor-config {
@@ -197,8 +201,6 @@ header h1 { font-size: 1.1rem; font-weight: 600; color: var(--accent); }
   font-size: 0.55rem;
   color: var(--muted);
   text-align: center;
-  overflow: hidden;
-  text-overflow: ellipsis;
   white-space: nowrap;
 }