Add company setting for whether to add vehicle to group on copy-clone

src/settings_type.h

@@ -660,6 +660,7 @@ struct CompanySettings {
 	bool infra_others_buy_in_depot[4];       ///< other companies can buy/autorenew in this companies depots (where infra sharing enabled)
 	uint16 timetable_autofill_rounding;      ///< round up timetable times to be a multiple of this number of ticks
 	bool advance_order_on_clone;             ///< when cloning a vehicle or copying/sharing an order list, advance the current order to a suitable point
+	bool copy_clone_add_to_group;            ///< whether to add cloned vehicles to the source vehicle's group, when cloning a vehicle without sharing orders
 };
 
 /** Debug settings. */