fix: Removes GetObjectsInRange and fixes boat planks closing (#1579)

## BREAKING CHANGE

- Deletes `map.GetObjectsInRange` and `map.GetObejctsInBounds`

### Notes

Developers are expected to enumerate mobiles and items separately now using `map.GetMobilesInRange` and `map.GetItemsInRange`. This helps keep the code streamlined so we don't have to maintain multiple copies of ref struct enumerators that do the same thing.


### Fixes

- [X] Fixes bug with planks closing
- [X] Fixes issue with iterating items/mobiles from a null map

Projects/UOContent/Multis/Boats/Plank.cs

@@ -231,17 +231,20 @@ namespace Server.Items
                 return false;
             }
 
-            var eable = GetObjectsInRange(0);
-
-            foreach (var obj in eable)
+            foreach (var item in GetItemsAt())
             {
-                if (obj == this)
+                if (item != this)
                 {
-                    return true;
+                    return false;
                 }
             }
 
-            return false;
+            foreach (var m in GetMobilesAt())
+            {
+                return false;
+            }
+
+            return true;
         }
 
         public void Close()