split into frontend and backend

frontend/lib/structs/destination.dart

@@ -0,0 +1,31 @@
+
+class Destination {
+  final double latitude;
+  final double longitude;
+  final String name;
+  final String description;
+  final DestinationType type;
+  final Duration duration;
+  final bool visited;
+
+  Destination({
+    required this.latitude,
+    required this.longitude,
+    required this.name,
+    required this.description,
+    required this.type,
+    required this.duration,
+    required this.visited,
+  });
+}
+
+
+class DestinationType {
+  final String name;
+  final String description;
+  
+  DestinationType({
+    required this.name,
+    required this.description,
+  });
+}