Core/Auras: Implement SPELL_AURA_MOD_DAMAGE_PERCENT_DONE_BY_TARGET_AURA_MECHANIC

Port From (https://github.com/TrinityCore/TrinityCore/commit/6a760de79b6dc9d821bd6dd2c362301c307991f0)

Source/Framework/Constants/Spells/SpellAuraConst.cs

@@ -256,7 +256,7 @@ namespace Framework.Constants
         ModAuraDurationByDispelNotStack = 246,
         CloneCaster = 247,
         ModCombatResultChance = 248,
-        ConvertRune = 249,
+        ModDamagePercentDoneByTargetAuraMechanic = 249,
         ModIncreaseHealth2 = 250,
         ModEnemyDodge = 251,
         ModSpeedSlowAll = 252,

Source/Game/Entities/Unit/Unit.Spells.cs

@@ -200,6 +200,14 @@ namespace Game.Entities
                 return false;
             });
 
+            // bonus against target aura mechanic
+            DoneTotalMod *= GetTotalAuraMultiplier(AuraType.ModDamagePercentDoneByTargetAuraMechanic, aurEff =>
+            {
+                if (victim.HasAuraWithMechanic(1ul << aurEff.GetMiscValue()))
+                    return true;
+                return false;
+            });
+
             // Add SPELL_AURA_MOD_DAMAGE_DONE_FOR_MECHANIC percent bonus
             if (spellEffectInfo.Mechanic != 0)
                 MathFunctions.AddPct(ref DoneTotalMod, GetTotalAuraModifierByMiscValue(AuraType.ModDamageDoneForMechanic, (int)spellEffectInfo.Mechanic));

Source/Game/Entities/Unit/Unit.cs

@@ -3966,6 +3966,14 @@ namespace Game.Entities
                 return false;
             });
 
+            // bonus against target aura mechanic
+            DoneTotalMod *= GetTotalAuraMultiplier(AuraType.ModDamagePercentDoneByTargetAuraMechanic, aurEff =>
+            {
+                if (victim.HasAuraWithMechanic(1ul << aurEff.GetMiscValue()))
+                    return true;
+                return false;
+            });
+
             // Add SPELL_AURA_MOD_DAMAGE_DONE_FOR_MECHANIC percent bonus
             if (spellEffectInfo != null && spellEffectInfo.Mechanic != 0)
                 MathFunctions.AddPct(ref DoneTotalMod, GetTotalAuraModifierByMiscValue(AuraType.ModDamageDoneForMechanic, (int)spellEffectInfo.Mechanic));