Align MKMini Gazebo steering and world scale

src/mkmini_gazebo_steering_plugin/src/steering_command_plugin.cpp

@@ -44,7 +44,18 @@ public:
       "/cmd_vel", rclcpp::QoS(10),
       [this](const geometry_msgs::msg::Twist::SharedPtr message) {
         std::lock_guard<std::mutex> lock(mutex_);
-        target_angle_ = std::clamp(message->angular.z, -0.5, 0.5);
+        // Twist.angular.z is yaw rate, not steering angle. Convert it using
+        // the signed vehicle speed so reverse Reeds-Shepp segments keep the
+        // same physical curvature as their planned path.
+        if (std::abs(message->linear.x) >= 0.01) {
+          target_angle_ = std::clamp(
+            std::atan(wheelbase_ * message->angular.z / message->linear.x),
+            -0.5,
+            0.5);
+        } else {
+          // Preserve the direct angle fallback used by manual J/L steering.
+          target_angle_ = std::clamp(message->angular.z, -0.5, 0.5);
+        }
         has_target_ = true;
       });
     update_connection_ = gazebo::event::Events::ConnectWorldUpdateBegin(