Extract preview dual pass live body

src/node_stroke_preview.h

@@ -59,6 +59,13 @@ public:
         bool copy_stroke_destination,
         float zoom,
         const glm::vec2& size);
+    void execute_stroke_draw_immediate_dual_pass(
+        const Brush& brush,
+        const pp::panopainter::LegacyNodeStrokePreviewPassOrchestrationPlan& pass_orchestration,
+        std::shared_ptr<Brush> dual_brush,
+        bool copy_stroke_destination,
+        float zoom,
+        const glm::vec2& size);
     void draw_stroke();
     void draw_stroke_immediate();
     Image render_to_image();