Make world border more aligned

src/main/java/eu/m724/tweaks/worldborder/WorldBorderExpanderListener.java

@@ -17,6 +17,13 @@ public class WorldBorderExpanderListener implements Listener {
     public void onWorldLoad(WorldLoadEvent event) {
         ServerLevel level = ((CraftWorld) event.getWorld()).getHandle();
 
+        if (level.getWorldBorder().getSize() < 5.9999968E7D) {
+            // if the world border was modified we don't touch it
+            return;
+        }
+
         level.getWorldBorder().setAbsoluteMaxSize(30000000);
+        // to align with player hitbox because player can't go beyond 30m - 1 and player's hitbox is 0.6 wide so we make it "hug" the border
+        level.getWorldBorder().setSize(59999998.6);
     }
 }