feat: added GtfsNetworkSchema (#1660)

* added GtfsNetworkSchema

* formatted code

* networks.txt is not required

---------

Co-authored-by: jcpitre <106176106+jcpitre@users.noreply.github.com>

main/src/main/java/org/mobilitydata/gtfsvalidator/report/model/FeedMetadata.java

@@ -57,6 +57,7 @@ public class FeedMetadata {
           new Pair<>("Zone-Based Fares", GtfsArea.FILENAME),
           new Pair<>("Transfer Fares", GtfsFareTransferRule.FILENAME),
           new Pair<>("Time-Based Fares", GtfsTimeframe.FILENAME),
+          new Pair<>("Route-Based Fares", GtfsNetwork.FILENAME),
           new Pair<>("Levels", GtfsLevel.FILENAME));
 
   protected FeedMetadata() {}
@@ -185,9 +186,10 @@ private void loadRouteBasedFaresComponent(GtfsFeedContainer feedContainer) {
     specFeatures.put(
         "Route-Based Fares",
         hasAtLeastOneRecordForFields(
-            feedContainer,
-            GtfsRoute.FILENAME,
-            List.of((Function<GtfsRoute, Boolean>) GtfsRoute::hasNetworkId)));
+                feedContainer,
+                GtfsRoute.FILENAME,
+                List.of((Function<GtfsRoute, Boolean>) GtfsRoute::hasNetworkId))
+            || hasAtLeastOneRecordInFile(feedContainer, GtfsNetwork.FILENAME));
   }
 
   private void loadBlocksComponent(GtfsFeedContainer feedContainer) {

main/src/main/java/org/mobilitydata/gtfsvalidator/table/GtfsNetworkSchema.java

@@ -0,0 +1,14 @@
+package org.mobilitydata.gtfsvalidator.table;
+
+import org.mobilitydata.gtfsvalidator.annotation.*;
+
+@GtfsTable("networks.txt")
+public interface GtfsNetworkSchema extends GtfsEntity {
+  @FieldType(FieldTypeEnum.ID)
+  @PrimaryKey
+  @Required
+  String networkId();
+
+  @MixedCase
+  String networkName();
+}