Core/Commands: Allow using display ids higher than std::numeric_limits<uint16>::max() for .modify morph command (#21022)

src/server/scripts/Commands/cs_modify.cpp

@@ -1023,7 +1023,7 @@ public:
         if (!*args)
             return false;
 
-        uint16 display_id = (uint16)atoi((char*)args);
+        uint32 display_id = (uint32)atoi((char*)args);
 
         Unit* target = handler->getSelectedUnit();
         if (!target)