Add functionality to fetch devices by room ID

Added a new method in DevicesCubit to fetch devices by room ID and updated
related classes and API calls to support this functionality.

lib/services/api/api_links_endpoints.dart

@@ -16,6 +16,7 @@ abstract class ApiEndpoints {
 
   // Devices
   static const String control = '$baseUrl/device/control';
+  static const String devicesByRoom = '$baseUrl/device/room';
 
   //groups
   static const String groups = '$baseUrl/group';