Scheduler refinements

Core/Entities/Team.cs

@@ -4,7 +4,8 @@ namespace Core.Entities;
 public class Team
 {
     public int Id { get; set; }
-    
+
+	[Required]
     public EventDefinition Event { get; set; }
 
     public List<Student> Students { get; set; } = [];
@@ -47,7 +48,7 @@ public class Team
 	{
 		var studentsToOmitList = studentsToOmit.ToList();
 		var omittedStudents = Students.Where(studentsToOmitList.Contains).ToList();
-		if (!omittedStudents.Any())
+		if (omittedStudents.Count == 0)
 			return new Team{Captain = Captain, Event = Event, Students = Students.ToList(), Identifier = Identifier};
 
 		var remainingStudents = Students.Where(s => !studentsToOmitList.Contains(s)).ToList();