Added a simple read-only TableModel and made it accessible via GenericCore.

Basically like in this tutorial: https://doc.qt.io/qt-6/modelview.html#2-1-a-read-only-table

model/tablemodel.h

@@ -0,0 +1,18 @@
+#ifndef TABLEMODEL_H
+#define TABLEMODEL_H
+
+#include <QAbstractTableModel>
+
+class TableModel : public QAbstractTableModel {
+ public:
+  explicit TableModel(QObject* parent = nullptr);
+
+  /// QAbstractItemModel interface
+ public:
+  int rowCount(const QModelIndex& parent) const override;
+  int columnCount(const QModelIndex& parent) const override;
+  QVariant data(const QModelIndex& index, int role) const override;
+  QVariant headerData(int section, Qt::Orientation orientation, int role) const override;
+};
+
+#endif  // TABLEMODEL_H