Implemented DK_DRAGONIC_BREATH (#7985)

Deals normal long ranged physical damage to the target.
    Can only be used when riding dragon.
    Deals additional damage depends on user's MaxHP and MaxSP.
    Affected by Hit/Flee calculation.
    Ignores physical defense.
    Damage property depends on weapon property.
    Affected by attack modifiers (such as race modifier).
    Recovers 2 AP.
    When using while under Dragonic Aura buff, increases influence of MaxHP and MaxSP in skill damage.
    Fixed casting time : 0.5 seconds (based on level 10).
    Variable Casting time : 2 seconds (based on level 10).
    Cooldown: 0.5 seconds (based on level 10).
    Global cool time : 0.15 seconds (based on level 10).

Co-authored-by: Lemongrass3110 <lemongrass@kstp.at>

Credit to @datawulf

src/map/skill.cpp

@@ -5616,6 +5616,7 @@ int skill_castend_damage_id (struct block_list* src, struct block_list *bl, uint
 	case DK_SERVANT_W_DEMOL:
 	case DK_MADNESS_CRUSHER:
 	case DK_HACKANDSLASHER:
+	case DK_DRAGONIC_BREATH:
 	case AG_CRIMSON_ARROW_ATK:
 	case AG_DESTRUCTIVE_HURRICANE:
 	case AG_SOUL_VC_STRIKE:
@@ -5735,6 +5736,7 @@ int skill_castend_damage_id (struct block_list* src, struct block_list *bl, uint
 				case GN_CARTCANNON:
 				case SU_SCRATCH:
 				case BO_MAYHEMIC_THORNS:
+				case DK_DRAGONIC_BREATH:
 				case DK_HACKANDSLASHER:
 				case MT_SPARK_BLASTER:
 					clif_skill_nodamage(src,bl,skill_id,skill_lv,1);