Add live pass sampler dispatch helper coverage

src/canvas.cpp

@@ -732,7 +732,7 @@ void Canvas::stroke_draw()
         },
     };
     const pp::panopainter::LegacyCanvasStrokeSamplerDispatch live_pass_sampler_dispatch =
-        pp::panopainter::make_legacy_canvas_stroke_sampler_dispatch(
+        pp::panopainter::make_legacy_canvas_stroke_live_pass_sampler_dispatch(
             [&](int slot) {
                 m_sampler_brush.bind(slot);
             },

src/legacy_canvas_stroke_execution_services.h

@@ -127,6 +127,28 @@ struct LegacyCanvasStrokeSamplerDispatch {
     std::function<void()> unbind_mixer_sampler;
 };
 
+[[nodiscard]] inline LegacyCanvasStrokeSamplerDispatch make_legacy_canvas_stroke_live_pass_sampler_dispatch(
+    std::function<void(int)> bind_brush_tip_sampler,
+    std::function<void()> unbind_brush_tip_sampler,
+    std::function<void(int)> bind_stroke_destination_sampler,
+    std::function<void()> unbind_stroke_destination_sampler,
+    std::function<void(int)> bind_pattern_sampler,
+    std::function<void()> unbind_pattern_sampler,
+    std::function<void(int)> bind_mixer_sampler,
+    std::function<void()> unbind_mixer_sampler)
+{
+    return LegacyCanvasStrokeSamplerDispatch {
+        .bind_brush_tip_sampler = std::move(bind_brush_tip_sampler),
+        .unbind_brush_tip_sampler = std::move(unbind_brush_tip_sampler),
+        .bind_stroke_destination_sampler = std::move(bind_stroke_destination_sampler),
+        .unbind_stroke_destination_sampler = std::move(unbind_stroke_destination_sampler),
+        .bind_pattern_sampler = std::move(bind_pattern_sampler),
+        .unbind_pattern_sampler = std::move(unbind_pattern_sampler),
+        .bind_mixer_sampler = std::move(bind_mixer_sampler),
+        .unbind_mixer_sampler = std::move(unbind_mixer_sampler),
+    };
+}
+
 [[nodiscard]] inline LegacyCanvasStrokeSamplerDispatch make_legacy_canvas_stroke_sampler_dispatch(
     std::function<void(int)> bind_brush_tip_sampler,
     std::function<void()> unbind_brush_tip_sampler,