fix(Scripts/UtgardePinnacle): Fix Skadi Poisoned Spear not applying DOT in Heroic (#25364)

Co-authored-by: Claude Opus 4.6 <noreply@anthropic.com>

data/sql/updates/pending_db_world/fix_skadi_poisoned_spear_heroic.sql

@@ -0,0 +1,5 @@
+-- Fix Skadi Poisoned Spear not applying periodic DOT in Heroic mode.
+-- Spell 59331 is the heroic variant of 50255 (mapped via spelldifficulty_dbc),
+-- but the spell script was only registered for the normal version.
+DELETE FROM `spell_script_names` WHERE `spell_id` = 59331 AND `ScriptName` = 'spell_skadi_poisoned_spear';
+INSERT INTO `spell_script_names` (`spell_id`, `ScriptName`) VALUES (59331, 'spell_skadi_poisoned_spear');

src/server/scripts/Northrend/UtgardeKeep/UtgardePinnacle/boss_skadi.cpp

@@ -533,7 +533,7 @@ class spell_skadi_launch_harpoon : public SpellScript
     }
 };
 
-// 50255 - Poisoned Spear
+// 50255, 59331 - Poisoned Spear
 class spell_skadi_poisoned_spear : public SpellScript
 {
     PrepareSpellScript(spell_skadi_poisoned_spear);