Build system changed to Cmake, ORM changed to QxORM, Qt6 compatibility.

shop/directsaleitem.h

@@ -5,7 +5,7 @@
 #include <QString>
 #include "ishopitem.h"
 
-class DirectSaleItem : public QObject, public IShopItem
+class DirectSaleItem : public IShopItem
 {
     Q_OBJECT
     Q_PROPERTY(QString name READ name WRITE setName)
@@ -22,7 +22,7 @@ public slots:
 
     // IShopItem interface
 public:
-    int id() override;
+    long id() override;
     QString name() override;
     QString shortName() override;
     QDecDouble unitPrice() override;