fix: Resolve compiler warnings and errors

Intersect.Editor/Forms/Controls/MapTreeList.cs

@@ -12,7 +12,7 @@ public partial class MapTreeList : UserControl
     private readonly Dictionary<MapListItem, TreeNode> _nodeLookup = new();
 
     //Cross Thread Delegates
-    public delegate void TryUpdateMapList(Guid selectMap, List<Guid> restrictMaps = null);
+    public delegate void TryUpdateMapList(Guid selectMap, List<Guid>? restrictMaps = null);
 
     public bool Chronological = false;
 
@@ -406,7 +406,7 @@ private void list_AfterCollapse(object sender, TreeViewEventArgs e)
         }
     }
 
-    public static void Scroll(Control control)
+    public static new void Scroll(Control control)
     {
         var pt = control.PointToClient(Cursor.Position);
 

Intersect.Editor/Forms/Controls/SearchableDarkTreeView.cs

@@ -56,7 +56,7 @@ public string SearchText
         }
     }
 
-    public virtual void Refresh()
+    public new virtual void Refresh()
     {
         UpdateNodes();
     }

Intersect.Editor/Forms/DockingElements/frmMapEditor.cs

@@ -1579,7 +1579,7 @@ public void SmartFillLayer(int x, int y)
         }
     }
 
-    private void SmartFillAttribute(int x, int y, string data = null, MapAttribute newAttribute = null)
+    private void SmartFillAttribute(int x, int y, string? data = null, MapAttribute? newAttribute = null)
     {
         if (x < 0 || x >= Options.Instance.Map.MapWidth || y < 0 || y >= Options.Instance.Map.MapHeight)
         {

Intersect.Editor/Forms/DockingElements/frmMapLayers.cs

@@ -753,7 +753,7 @@ private MapCritterAttribute CreateCritterAttribute()
         return critterAttribute;
     }
 
-    public MapAttribute PlaceAttribute(MapDescriptor mapDescriptor, int x, int y, MapAttribute attribute = null)
+    public MapAttribute PlaceAttribute(MapDescriptor mapDescriptor, int x, int y, MapAttribute? attribute = null)
     {
         if (attribute == null)
         {

Intersect.Editor/Forms/DockingElements/frmMapProperties.cs

@@ -40,7 +40,7 @@ private void InitLocalization()
         Text = Strings.MapProperties.title;
     }
 
-    public void Update()
+    public new void Update()
     {
         gridMapProperties.Refresh();
     }

Intersect.Editor/Forms/Editors/Events/Event Commands/Event_GraphicSelector.cs

@@ -31,7 +31,7 @@ public partial class EventGraphicSelector : UserControl
     public EventGraphicSelector(
         EventGraphic editingGraphic,
         FrmEvent eventEditor,
-        EventMoveRouteDesigner moveRouteDesigner = null,
+        EventMoveRouteDesigner? moveRouteDesigner = null,
         bool newMoveRouteAction = false
     )
     {

Intersect.Editor/Forms/Editors/Events/Event Commands/Event_MoveRouteDesigner.cs

@@ -30,7 +30,7 @@ public EventMoveRouteDesigner(
         MapDescriptor currentMap,
         EventDescriptor currentEvent,
         EventMoveRoute editingRoute,
-        SetMoveRouteCommand editingCommand = null,
+        SetMoveRouteCommand? editingCommand = null,
         bool disableRouteTarget = false
     )
     {

Intersect.Editor/Forms/Helpers/GridHelper.cs

@@ -14,7 +14,7 @@ public partial struct GridCell
 
     public Color? LabelColor { get; private set; }
 
-    public GridCell(int x, int y, Color? color = default, string label = null, Color? labelColor = default)
+    public GridCell(int x, int y, Color? color = default, string? label = null, Color? labelColor = default)
     {
         X = x;
         Y = y;

Intersect.Editor/Forms/frmMain.cs

@@ -553,7 +553,7 @@ public void MouseDownHandler(object sender, MouseEventArgs e)
     }
 
     //Update
-    public void Update()
+    public new void Update()
     {
         if (Globals.CurrentMap != null)
         {