feat: api endpoints and xml sync for contingents data

src/BusProNet/XmlLoader/TravelLoader.php

@@ -58,6 +58,7 @@ class TravelLoader extends AbstractLoader
         try {
             return $this->cache->get('bpn_travels_mapping', function (ItemInterface $item) {
                 $item->expiresAfter(3 * 60 * 60);
+                $item->tag(['xml-sync']);
 
                 $xmlFiles = $this
                     ->xmlExport