Address compiler warnings

Core/Calculation/EventAssignmentThresholds.cs

@@ -4,7 +4,7 @@ namespace Core.Calculation;
 
 public class EventAssignmentThresholds
 {
-    public EventDefinition Event { get; set; }
+    public EventDefinition Event { get; set; } = null!;
     public int TeamCount { get; set; }
     public int LowerBound { get; set; }
     public int UpperBound { get; set; }

Core/Calculation/TeamScheduleTimeSlot.cs

@@ -10,22 +10,22 @@ public class TeamScheduleTimeSlot
     /// <summary>
     /// Gets or sets the name of this time slot.
     /// </summary>
-    public string Name { get; set; }
+    public string Name { get; set; } = null!;
 
     /// <summary>
     /// Gets or sets the teams scheduled in this time slot.
     /// </summary>
-    public Team[] Teams;
+    public Team[] Teams = null!;
 
     /// <summary>
     /// Gets or sets the students who are not scheduled in any team during this time slot.
     /// </summary>
-    public Student[] UnscheduledStudents;
+    public Student[] UnscheduledStudents = null!;
 
     /// <summary>
     /// Gets or sets the students who have overlapping team meetings in this time slot.
     /// </summary>
-    public IEnumerable<(Student student, IEnumerable<Team> teams)> StudentOverlaps;
+    public IEnumerable<(Student student, IEnumerable<Team> teams)> StudentOverlaps = null!;
 
     /// <summary>
     /// Checks if a student has overlapping team meetings in this time slot.