Core/Entities: force CombatManager revalidation after applying charm

"Safely" goes through all combat references validating if in fact the unit should remain in combat or not
Any edge case that may get affected by this, are scenarios in which the charmed unit must keep the combat and threat references prior to their charm.... I can't think of any.
-> And honestly if there was any such case... imo it should be handled script wise, not core wise.

closes #31747
updates #30169

Author: ccrs

src/server/game/Entities/Unit/Unit.cpp

@@ -11575,6 +11575,7 @@ bool Unit::SetCharmedBy(Unit* charmer, CharmType type, AuraApplication const* au
 
     // Set charmed
     charmer->SetCharm(this, true);
+    m_combatManager.RevalidateCombat();
 
     if (Player* player = ToPlayer())
     {