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/EditorContext.cpp

@@ -2,6 +2,7 @@
 #include "Composition/EditorShellAssetBuilder.h"
 #include "Scene/EditorSceneRuntime.h"
 #include "Composition/EditorPanelIds.h"
+#include <XCEditor/Foundation/UIEditorRuntimeTrace.h>
 #include <sstream>
 #include <utility>
 
@@ -11,6 +12,7 @@ namespace {
 
 using ::XCEngine::UI::Editor::BuildEditorShellShortcutManager;
 using ::XCEngine::UI::Editor::UIEditorWorkspacePanelPresentationModel;
+using ::XCEngine::UI::Editor::AppendUIEditorRuntimeTrace;
 
 std::string ComposeStatusText(
     std::string_view status,
@@ -41,8 +43,14 @@ UIEditorWorkspacePanelPresentationModel* FindMutablePresentation(
 } // namespace
 
 bool EditorContext::Initialize(const std::filesystem::path& repoRoot) {
+    AppendUIEditorRuntimeTrace("startup", "EditorContext::Initialize begin");
     m_shellAsset = BuildEditorApplicationShellAsset(repoRoot);
+    AppendUIEditorRuntimeTrace("startup", "BuildEditorApplicationShellAsset complete");
     m_shellValidation = ValidateEditorShellAsset(m_shellAsset);
+    AppendUIEditorRuntimeTrace(
+        "startup",
+        std::string("ValidateEditorShellAsset complete valid=") +
+            (m_shellValidation.IsValid() ? "1" : "0"));
     if (!m_shellValidation.IsValid()) {
         return false;
     }
@@ -53,10 +61,14 @@ bool EditorContext::Initialize(const std::filesystem::path& repoRoot) {
     m_commandFocusService = {};
     m_selectionService = {};
     m_projectRuntime = {};
+    AppendUIEditorRuntimeTrace("startup", "EditorProjectRuntime::Initialize begin");
     m_projectRuntime.Initialize(repoRoot);
+    AppendUIEditorRuntimeTrace("startup", "EditorProjectRuntime::Initialize end");
     m_projectRuntime.BindSelectionService(&m_selectionService);
     m_sceneRuntime = {};
+    AppendUIEditorRuntimeTrace("startup", "EditorSceneRuntime::Initialize begin");
     m_sceneRuntime.Initialize(m_session.projectRoot);
+    AppendUIEditorRuntimeTrace("startup", "EditorSceneRuntime::Initialize end");
     m_sceneRuntime.BindSelectionService(&m_selectionService);
     ResetEditorColorPickerToolState(m_colorPickerToolState);
     SyncSessionFromSelectionService();
@@ -69,6 +81,7 @@ bool EditorContext::Initialize(const std::filesystem::path& repoRoot) {
     m_shellServices.commandDispatcher = &m_shortcutManager.GetCommandDispatcher();
     m_shellServices.shortcutManager = &m_shortcutManager;
     SetReadyStatus();
+    AppendUIEditorRuntimeTrace("startup", "EditorContext::Initialize end");
     return true;
 }