add filter by network for legs, add full export for traction

test/helpers/fake_services.dart

@@ -201,6 +201,7 @@ class FakeDataService extends DataService {
     String? dateRangeEnd,
     bool append = false,
     bool unallocatedOnly = false,
+    List<String> networkFilter = const [],
   }) async {}
 
   @override
@@ -231,6 +232,9 @@ class FakeDataService extends DataService {
   @override
   Future<void> fetchPendingLocoCount() async {}
 
+  @override
+  Future<void> fetchStationNetworks() async {}
+
   @override
   Future<Map<String, dynamic>?> fetchClassStats(String locoClass) async {
     return TestData.classStats;