feat(api/webhook): logging for journey recording, proper HTTP status codes

src/api/db_vendo_navigator.rs

@@ -17,6 +17,7 @@ pub async fn get_railcar_identifier_by_journey(
 }
 
 fn find_railcar_identifier(train_ordering: TrainOrdering) -> Result<u64, ResolveTripNumberError> {
+    //TODO: refactor - trainsets can consist out of several trains
     let trainset = train_ordering.train_sets.first()
         .ok_or(ResolveTripNumberError::Api("No items in field 'fahrzeuggruppe'".to_string()))?;
     let identifier_str = trainset.identifier.to_owned();