fix rent calculation

lib/game.h

@@ -28,6 +28,13 @@ class InputManager;
  */
 class Game {
 public:
+    enum class Type {
+        BASE,
+        MONOPOLY_DICE,
+        MONOPOLY_PROPERTY,
+        MONOPOLY_BOARD
+    };
+
     /**
      * @brief Construct a new Game
      * @param width Display width in pixels
@@ -83,6 +90,11 @@ public:
      */
     virtual bool wants_to_exit() const { return false; }
 
+    /**
+     * @brief Get the type of game for safe downcasting without RTTI
+     */
+    virtual Type get_type() const { return Type::BASE; }
+
 protected:
     // Display dimensions
     uint16_t width;