feat(xcui): advance core and editor validation flow

new_editor/src/editor/UIEditorWorkspaceModel.cpp

@@ -1,3 +1,4 @@
+#include <XCNewEditor/Editor/UIEditorPanelRegistry.h>
 #include <XCNewEditor/Editor/UIEditorWorkspaceModel.h>
 
 #include <cmath>
@@ -21,6 +22,18 @@ bool IsValidSplitRatio(float value) {
     return std::isfinite(value) && value > 0.0f && value < 1.0f;
 }
 
+const UIEditorPanelDescriptor& RequirePanelDescriptor(
+    const UIEditorPanelRegistry& registry,
+    std::string_view panelId) {
+    if (const UIEditorPanelDescriptor* descriptor = FindUIEditorPanelDescriptor(registry, panelId);
+        descriptor != nullptr) {
+        return *descriptor;
+    }
+
+    static const UIEditorPanelDescriptor fallbackDescriptor = {};
+    return fallbackDescriptor;
+}
+
 const UIEditorWorkspacePanelState* FindPanelRecursive(
     const UIEditorWorkspaceNode& node,
     std::string_view panelId) {
@@ -192,6 +205,21 @@ UIEditorWorkspaceValidationResult ValidateNodeRecursive(
 
 } // namespace
 
+UIEditorWorkspaceModel BuildDefaultEditorShellWorkspaceModel() {
+    const UIEditorPanelRegistry registry = BuildDefaultEditorShellPanelRegistry();
+    const UIEditorPanelDescriptor& rootPanel =
+        RequirePanelDescriptor(registry, "editor-foundation-root");
+
+    UIEditorWorkspaceModel workspace = {};
+    workspace.root = BuildUIEditorWorkspacePanel(
+        "editor-foundation-root-node",
+        rootPanel.panelId,
+        rootPanel.defaultTitle,
+        rootPanel.placeholder);
+    workspace.activePanelId = rootPanel.panelId;
+    return workspace;
+}
+
 UIEditorWorkspaceNode BuildUIEditorWorkspacePanel(
     std::string nodeId,
     std::string panelId,