feat(Core/Hooks): Add parameter to detect XP origin for OnGiveXP hook. (#16109)

Added enum parameter to detect where XP originated from.

src/server/game/Entities/Player/Player.h

@@ -995,6 +995,16 @@ enum PlayerCommandStates
     CHEAT_WATERWALK = 0x10
 };
 
+// Used for OnGiveXP PlayerScript hook
+enum PlayerXPSource
+{
+    XPSOURCE_KILL = 0,
+    XPSOURCE_QUEST = 1,
+    XPSOURCE_QUEST_DF = 2,
+    XPSOURCE_EXPLORE = 3,
+    XPSOURCE_BATTLEGROUND = 4
+};
+
 enum InstantFlightGossipAction
 {
     GOSSIP_ACTION_TOGGLE_INSTANT_FLIGHT = 500