fix(timeline): Only allows seek between bounds

Author: bdlukaa

lib/screens/events_timeline/desktop/timeline.dart

@@ -359,7 +359,13 @@ class Timeline extends ChangeNotifier {
   DateTime get currentDate => date.add(currentPosition);
 
   void seekTo(Duration position) {
-    currentPosition = position;
+    if (position < Duration.zero) {
+      currentPosition = Duration.zero;
+    } else if (position > endPosition) {
+      currentPosition = endPosition;
+    } else {
+      currentPosition = position;
+    }
     notifyListeners();
 
     forEachEvent((tile, event) async {
@@ -375,8 +381,6 @@ class Timeline extends ChangeNotifier {
     });
   }
 
-  // TODO(bdlukaa): Only make it possible to seek between bounds.
-  //                Currently, is is possible to seek before and after the day.
   /// Seeks forward by [duration]
   void seekForward([Duration duration = const Duration(seconds: 15)]) =>
       seekTo(currentPosition + duration);