fix(Core/Battlegrounds): keep BG spirit guides Alive (#25535)

Co-authored-by: Shauren <shauren.trinity@gmail.com>
Co-authored-by: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

src/server/game/Battlegrounds/Battleground.cpp

@@ -1711,7 +1711,6 @@ bool Battleground::AddSpiritGuide(uint32 type, float x, float y, float z, float
 
     if (Creature* creature = AddCreature(entry, type, x, y, z, o))
     {
-        creature->setDeathState(DeathState::Dead);
         creature->SetGuidValue(UNIT_FIELD_CHANNEL_OBJECT, creature->GetGUID());
         // aura
         /// @todo: Fix display here