refactor: update Flight model casts and relations

app/Enums/FlightStatus.php

@@ -0,0 +1,13 @@
+<?php
+
+namespace App\Enums;
+
+enum FlightStatus:int
+{
+    case AVAILABLE = 0;
+
+    case FULL = 1;
+    case CANCELLED = 2;
+    case DRAFT = 3;
+    case DELAYED = 4;
+}

app/Enums/FlightTripType.php

@@ -0,0 +1,9 @@
+<?php
+
+namespace App\Enums;
+
+enum FlightTripType: int
+{
+    case ONEWAY = 0;
+    case ROUNDTRIP = 1;
+}