World level updates without needing to restart

src/main/java/emu/grasscutter/command/commands/SetWorldLevelCommand.java

@@ -29,7 +29,7 @@ public final class SetWorldLevelCommand implements CommandHandler {
 
             // Set in both world and player props
             sender.getWorld().setWorldLevel(level);
-            sender.setProperty(PlayerProperty.PROP_PLAYER_WORLD_LEVEL, level);
+            sender.setWorldLevel(level);
 
             sender.dropMessage("World level set to " + level + ".");
         } catch (NumberFormatException ignored) {

src/main/java/emu/grasscutter/game/GenshinPlayer.java

@@ -268,6 +268,11 @@ public class GenshinPlayer {
 		return this.getProperty(PlayerProperty.PROP_PLAYER_WORLD_LEVEL);
 	}
 	
+	public void setWorldLevel(int level) {
+		this.setProperty(PlayerProperty.PROP_PLAYER_WORLD_LEVEL, level);
+		this.sendPacket(new PacketPlayerPropNotify(this, PlayerProperty.PROP_PLAYER_WORLD_LEVEL));
+	}
+
 	public int getPrimogems() {
 		return this.getProperty(PlayerProperty.PROP_PLAYER_HCOIN);
 	}