style: selected marker turns orange

Bold label + ring alone weren't enough to distinguish a selected
marker from the default red flags. The .selected rule now overrides
--marker-color to #f59e0b (amber) with !important so per-marker color
overrides also yield to selection.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

src/components/Timeline.vue

@@ -2930,7 +2930,16 @@ onBeforeUnmount(() => {
   text-overflow: ellipsis;
 }
 
-.timeline-marker:hover .timeline-marker-flag,
+.timeline-marker:hover .timeline-marker-flag {
+  box-shadow: 0 0 0 1.5px var(--range-hover);
+}
+
+/* Selected marker: override to orange (incl. per-marker color overrides)
+   so the selection is obvious against the default red. */
+.timeline-marker.selected {
+  --marker-color: #f59e0b !important;
+}
+
 .timeline-marker.selected .timeline-marker-flag {
   box-shadow: 0 0 0 1.5px var(--range-hover);
 }