feat(command-zone): add abstract zone menu base class

Introduce AbstractZoneMenu - a base class for zone-specific context
menus that provides common functionality.

This abstraction:
- Reduces code duplication across zone menu implementations
- Establishes consistent menu behavior patterns
- Provides foundation for CommandZoneMenu implementation

Small foundational commit to keep the menu hierarchy clean.

cockatrice/src/game/player/menu/abstract_zone_menu.h

@@ -0,0 +1,54 @@
+/**
+ * @file abstract_zone_menu.h
+ * @ingroup GameMenusZones
+ * @brief Abstract interface for zone menus with common shortcut management.
+ *
+ * This interface enables polymorphic iteration over heterogeneous menu types
+ * for keyboard shortcut activation/deactivation and UI translation.
+ */
+
+#ifndef COCKATRICE_ABSTRACT_ZONE_MENU_H
+#define COCKATRICE_ABSTRACT_ZONE_MENU_H
+
+/**
+ * @class AbstractZoneMenu
+ * @brief Interface for zone menus that support keyboard shortcuts and translation.
+ *
+ * Provides a common contract for menus that need to:
+ * - Activate/deactivate keyboard shortcuts based on game focus
+ * - Update UI text when language changes
+ *
+ * Menus implementing this interface can be stored polymorphically
+ * in PlayerMenu for batch operations.
+ */
+class AbstractZoneMenu
+{
+public:
+    virtual ~AbstractZoneMenu() = default;
+
+    /**
+     * @brief Enable keyboard shortcuts for this menu's actions.
+     *
+     * Called when this player becomes the active/focused player.
+     * Implementations should apply shortcut keys to their QActions.
+     */
+    virtual void setShortcutsActive() = 0;
+
+    /**
+     * @brief Disable keyboard shortcuts for this menu's actions.
+     *
+     * Called when focus moves away from this player.
+     * Implementations should clear shortcut keys from their QActions.
+     */
+    virtual void setShortcutsInactive() = 0;
+
+    /**
+     * @brief Update all translatable text in the menu.
+     *
+     * Called when the application language changes.
+     * Implementations should update menu titles, action text, and tooltips.
+     */
+    virtual void retranslateUi() = 0;
+};
+
+#endif // COCKATRICE_ABSTRACT_ZONE_MENU_H