add timeline

lib/components/pages/traction.dart

@@ -574,6 +574,12 @@ class _TractionPageState extends State<TractionPage> {
                   icon: const Icon(Icons.info_outline),
                   label: const Text('Details'),
                 ),
+                const SizedBox(width: 8),
+                TextButton.icon(
+                  onPressed: () => _openTimeline(loco),
+                  icon: const Icon(Icons.timeline),
+                  label: const Text('Timeline'),
+                ),
                 const Spacer(),
                 if (widget.selectionMode)
                   TextButton.icon(
@@ -692,6 +698,14 @@ class _TractionPageState extends State<TractionPage> {
     return (background, foreground);
   }
 
+  void _openTimeline(LocoSummary loco) {
+    final label = '${loco.locoClass} ${loco.number}'.trim();
+    context.push(
+      '/traction/${loco.id}/timeline',
+      extra: {'label': label},
+    );
+  }
+
   Future<void> _showLocoInfo(LocoSummary loco) async {
     await showModalBottomSheet(
       context: context,