Core/Items: Check required level to use items including any bonuses that modify it

Port From (https://github.com/TrinityCore/TrinityCore/commit/b702401978928781249798dd607b6c6fbd10f122)

Source/Game/Entities/Player/Player.Items.cs

@@ -1447,7 +1447,7 @@ namespace Game.Entities
             }
             return InventoryResult.ItemNotFound;
         }
-        public InventoryResult CanUseItem(ItemTemplate proto)
+        public InventoryResult CanUseItem(ItemTemplate proto, bool skipRequiredLevelCheck = false)
         {
             // Used by group, function GroupLoot, to know if a prototype can be used by a player
 
@@ -1477,7 +1477,7 @@ namespace Game.Entities
             if (proto.GetRequiredSpell() != 0 && !HasSpell(proto.GetRequiredSpell()))
                 return InventoryResult.ProficiencyNeeded;
 
-            if (GetLevel() < proto.GetBaseRequiredLevel())
+            if (!skipRequiredLevelCheck && GetLevel() < proto.GetBaseRequiredLevel())
                 return InventoryResult.CantEquipLevelI;
 
             // If World Event is not active, prevent using event dependant items

Source/Game/Spells/Spell.cs

@@ -6046,7 +6046,7 @@ namespace Game.Spells
                                 return SpellCastResult.ItemNotFound;
 
                             // required level has to be checked also! Exploit fix
-                            if (targetItem.GetTemplate().GetBaseItemLevel() < m_spellInfo.BaseLevel || (targetItem.GetTemplate().GetBaseRequiredLevel() != 0 && (uint)targetItem.GetTemplate().GetBaseRequiredLevel() < m_spellInfo.BaseLevel))
+                            if (targetItem.GetItemLevel(targetItem.GetOwner()) < m_spellInfo.BaseLevel || (targetItem.GetRequiredLevel() != 0 && targetItem.GetRequiredLevel() < m_spellInfo.BaseLevel))
                                 return SpellCastResult.Lowlevel;
 
                             bool isItemUsable = false;