RouteStatus enum

Enum describing possible router states. Referenced from AsyncRouteListener.

Example:

// Demonstrate all RouteStatus values
print("Available RouteStatus values:");
List<RouteStatus> allStatuses = [
 RouteStatus.missingGraph,
 RouteStatus.missingPosition,
 RouteStatus.missingRoute,
 RouteStatus.missingProjection,
 RouteStatus.newRoute,
];
for (RouteStatus status in allStatuses) {
 print("  - $status: ${status.toString()}");
}
// Demonstrate status checking
RouteStatus testStatus = RouteStatus.newRoute;
switch (testStatus) {
 case RouteStatus.newRoute:
   print("Router is ready for navigation");
   break;
 case RouteStatus.missingGraph:
   print("Router is missing the route graph");
   break;
 case RouteStatus.missingPosition:
   print("Router is missing the current position");
   break;
 case RouteStatus.missingProjection:
   print("Current position is off the route graph");
   break;
 case RouteStatus.missingRoute:
   print("Router unable to find the route to the destination point");
   break;
}