XpNoCooldown and combineXpOrbs refactor (#1149)

* - Fix xpNoCooldown to work as it did in 1.17-
- Remove XPcombine
- Use vanilla merge methods

* Remove debug code

* fix: rollback sort carpet.mixins.json

* rework: nerf xp cooldown absorption a little

* remove: combineXpOrbs
fix: xpCooldown

* revert renames

* fix newlines

* fix: wrong implementation for absorption

* add missing `private` keyword

* fix: player xp cooldown set wrongly

* fix: injection point to be within condition

src/main/java/carpet/CarpetSettings.java

@@ -184,10 +184,6 @@ public class CarpetSettings
     @Rule( desc = "Players absorb XP instantly, without delay", category = CREATIVE )
     public static boolean xpNoCooldown = false;
 
-
-    @Rule( desc = "XP orbs combine with other into bigger orbs", category = FEATURE )
-    public static boolean combineXPOrbs = false;
-
     @Rule(
             desc = "Empty shulker boxes can stack to 64 when dropped on the ground",
             extra = ".. or when manipulated inside the inventories",