[Game] Playmats (#7101)

* [Game] Playmats

Took 19 seconds

Took 1 minute

* [Playmats] Add fixed override and configurable fallbacks to settings.

Took 29 minutes

Took 43 seconds

* Add main to test.

Took 1 minute

Took 29 seconds

* Move settings to own group

Took 11 minutes

* Some attempts to refresh macOS compositor

Took 2 minutes

* Try something else

Took 17 minutes

* Don't manipulate live list

Took 11 minutes

* Change things about resolution, address comments.

Took 45 minutes

Took 12 minutes

* Comments.

Took 14 minutes

Took 8 seconds

* Re-order settings menu location

Took 2 minutes

* Rename PlaymatResolution to Info and add enums

Took 8 minutes

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Co-authored-by: Lukas Brübach <Bruebach.Lukas@bdosecurity.de>

cockatrice/src/interface/widgets/playmat/playmat_preview_widget.h

@@ -0,0 +1,35 @@
+#ifndef COCKATRICE_PLAYMAT_PREVIEW_WIDGET_H
+#define COCKATRICE_PLAYMAT_PREVIEW_WIDGET_H
+
+#include <QPixmap>
+#include <QWidget>
+#include <libcockatrice/deck_list/deck_list.h>
+
+/**
+ * @brief Preview widget that shows how a playmat card art will appear
+ *        across the combined table + stack play area.
+ *
+ * Renders a miniature mockup with the card art applied using the
+ * given PlaymatParams, including faint zone divider lines.
+ */
+class PlaymatPreviewWidget : public QWidget
+{
+    Q_OBJECT
+
+public:
+    explicit PlaymatPreviewWidget(QWidget *parent = nullptr);
+
+    void setPixmap(const QPixmap &pixmap);
+    void setParams(const PlaymatParams &params);
+    void setAttribution(const QString &attribution);
+
+protected:
+    void paintEvent(QPaintEvent *event) override;
+
+private:
+    QPixmap sourcePixmap;
+    PlaymatParams params;
+    QString attributionText;
+};
+
+#endif // COCKATRICE_PLAYMAT_PREVIEW_WIDGET_H