checkpoint(new_editor): native d3d12 ui path

Key node 1: move main-window UI presentation onto the D3D12 render loop with native UI renderer, text system, and texture host.

Key node 2: wire frame timing/FPS display, window runtime, swapchain presentation, and native screenshot capture around the new path.

Key node 3: carry editor shell/workspace/viewport/panel interaction updates needed by the new renderer and detached window flow.

Key node 4: pump async resource loads and scene bridge follow-up needed for scene content visibility in new_editor.

new_editor/app/Composition/EditorShellRuntime.cpp

@@ -49,7 +49,6 @@ void EditorShellRuntime::Initialize(
     m_projectPanel.SetBuiltInIcons(&m_builtInIcons);
     m_projectPanel.SetTextMeasurer(&textMeasurer);
     m_hierarchyPanel.Initialize();
-    m_projectPanel.Initialize(repoRoot);
 }
 
 void EditorShellRuntime::AttachViewportWindowRenderer(Ports::ViewportRenderPort& renderer) {
@@ -257,36 +256,120 @@ void AppendShellPopups(
 namespace XCEngine::UI::Editor::App {
 
 using ::XCEngine::UI::UIDrawList;
+using ::XCEngine::UI::UIDrawData;
+
+template<typename AppendFn>
+void AppendDrawPacket(
+    UIDrawData& drawData,
+    std::string debugName,
+    AppendFn&& appendFn) {
+    UIDrawList drawList(std::move(debugName));
+    appendFn(drawList);
+    if (!drawList.Empty()) {
+        drawData.AddDrawList(std::move(drawList));
+    }
+}
+
 void EditorShellRuntime::RenderRequestedViewports(
     const ::XCEngine::Rendering::RenderContext& renderContext) {
     m_viewportHostService.RenderRequestedViewports(renderContext);
 }
 
-void EditorShellRuntime::Append(UIDrawList& drawList) const {
+void EditorShellRuntime::Append(UIDrawData& drawData) const {
     const auto& metrics = ResolveUIEditorShellInteractionMetrics();
     const auto& palette = ResolveUIEditorShellInteractionPalette();
     const UIEditorShellComposeModel shellComposeModel =
         BuildShellComposeModelFromFrame(m_shellFrame);
-    AppendUIEditorShellCompose(
-        drawList,
-        m_shellFrame.shellFrame,
-        shellComposeModel,
-        m_shellInteractionState.composeState,
-        palette.shellPalette,
-        metrics.shellMetrics,
-        &m_builtInIcons);
-    m_consolePanel.Append(drawList);
-    m_colorPickerPanel.Append(drawList);
-    m_hierarchyPanel.Append(drawList);
-    m_inspectorPanel.Append(drawList);
-    m_projectPanel.Append(drawList);
-    m_sceneViewportFeature.Append(drawList);
-    AppendUIEditorShellComposeOverlay(
-        drawList,
-        m_shellFrame.shellFrame,
-        palette.shellPalette,
-        metrics.shellMetrics);
-    AppendShellPopups(drawList, m_shellFrame, palette, metrics);
+    AppendDrawPacket(
+        drawData,
+        "XCEditorShell.Compose.Base",
+        [&](UIDrawList& drawList) {
+            AppendUIEditorShellComposeBase(
+                drawList,
+                m_shellFrame.shellFrame,
+                shellComposeModel,
+                m_shellInteractionState.composeState,
+                palette.shellPalette,
+                metrics.shellMetrics,
+                &m_builtInIcons);
+        });
+    AppendDrawPacket(
+        drawData,
+        "XCEditorShell.Compose.Workspace",
+        [&](UIDrawList& drawList) {
+            AppendUIEditorWorkspaceCompose(
+                drawList,
+                m_shellFrame.workspaceInteractionFrame.composeFrame,
+                palette.shellPalette.dockHostPalette,
+                metrics.shellMetrics.dockHostMetrics,
+                palette.shellPalette.viewportPalette,
+                metrics.shellMetrics.viewportMetrics,
+                UIEditorWorkspaceComposeAppendOptions{
+                    true,
+                    false
+                });
+        });
+    AppendDrawPacket(
+        drawData,
+        "XCEditorShell.Compose.ViewportTextures",
+        [&](UIDrawList& drawList) {
+            AppendUIEditorWorkspaceComposeViewportTextures(
+                drawList,
+                m_shellFrame.workspaceInteractionFrame.composeFrame,
+                palette.shellPalette.viewportPalette);
+        });
+    AppendDrawPacket(
+        drawData,
+        "XCEditorShell.Compose.StatusBar",
+        [&](UIDrawList& drawList) {
+            AppendUIEditorShellComposeStatusBar(
+                drawList,
+                m_shellFrame.shellFrame,
+                shellComposeModel,
+                m_shellInteractionState.composeState,
+                palette.shellPalette,
+                metrics.shellMetrics);
+        });
+    AppendDrawPacket(
+        drawData,
+        "XCEditorPanel.Console",
+        [&](UIDrawList& drawList) { m_consolePanel.Append(drawList); });
+    AppendDrawPacket(
+        drawData,
+        "XCEditorPanel.ColorPicker",
+        [&](UIDrawList& drawList) { m_colorPickerPanel.Append(drawList); });
+    AppendDrawPacket(
+        drawData,
+        "XCEditorPanel.Hierarchy",
+        [&](UIDrawList& drawList) { m_hierarchyPanel.Append(drawList); });
+    AppendDrawPacket(
+        drawData,
+        "XCEditorPanel.Inspector",
+        [&](UIDrawList& drawList) { m_inspectorPanel.Append(drawList); });
+    AppendDrawPacket(
+        drawData,
+        "XCEditorPanel.Project",
+        [&](UIDrawList& drawList) { m_projectPanel.Append(drawList); });
+    AppendDrawPacket(
+        drawData,
+        "XCEditorPanel.SceneOverlay",
+        [&](UIDrawList& drawList) { m_sceneViewportFeature.Append(drawList); });
+    AppendDrawPacket(
+        drawData,
+        "XCEditorShell.Compose.Overlay",
+        [&](UIDrawList& drawList) {
+            AppendUIEditorShellComposeOverlay(
+                drawList,
+                m_shellFrame.workspaceInteractionFrame.composeFrame,
+                palette.shellPalette,
+                metrics.shellMetrics);
+        });
+    AppendDrawPacket(
+        drawData,
+        "XCEditorShell.Popups",
+        [&](UIDrawList& drawList) {
+            AppendShellPopups(drawList, m_shellFrame, palette, metrics);
+        });
 }
 
 } // namespace XCEngine::UI::Editor::App
@@ -664,7 +747,6 @@ void ApplyViewportFramesToShellFrame(
         };
 
     applyToViewportFrames(shellFrame.workspaceInteractionFrame.composeFrame.viewportFrames);
-    applyToViewportFrames(shellFrame.shellFrame.workspaceFrame.viewportFrames);
 }
 
 } // namespace XCEngine::UI::Editor::App