new_editor: isolate project panel state and harden runtime reset

new_editor/app/Features/Project/ProjectBrowserModel.cpp

@@ -553,7 +553,16 @@ std::string RemapMovedItemId(
 
 } // namespace
 
+void ProjectBrowserModel::Reset() {
+    m_assetsRootPath.clear();
+    m_folderEntries.clear();
+    m_treeItems.clear();
+    m_assetEntries.clear();
+    m_currentFolderId.clear();
+}
+
 void ProjectBrowserModel::Initialize(const std::filesystem::path& repoRoot) {
+    Reset();
     m_assetsRootPath = (repoRoot / "project/Assets").lexically_normal();
     TraceProjectBrowser("ProjectBrowserModel::Initialize assetsRoot=" + PathToUtf8String(m_assetsRootPath));
     std::error_code errorCode = {};
@@ -571,21 +580,6 @@ void ProjectBrowserModel::Initialize(const std::filesystem::path& repoRoot) {
         std::to_string(m_assetEntries.size()));
 }
 
-void ProjectBrowserModel::SetFolderIcon(const ::XCEngine::UI::UITextureHandle& icon) {
-    if (m_folderIcon.nativeHandle == icon.nativeHandle &&
-        m_folderIcon.width == icon.width &&
-        m_folderIcon.height == icon.height &&
-        m_folderIcon.kind == icon.kind &&
-        m_folderIcon.resourceHandle == icon.resourceHandle) {
-        return;
-    }
-
-    m_folderIcon = icon;
-    if (!m_assetsRootPath.empty()) {
-        RefreshFolderTree();
-    }
-}
-
 void ProjectBrowserModel::Refresh() {
     TraceProjectBrowser("ProjectBrowserModel::Refresh begin");
     RefreshFolderTree();
@@ -1307,7 +1301,6 @@ void ProjectBrowserModel::RefreshFolderTree() {
         item.label = folderEntry.label;
         item.depth = depth;
         item.forceLeaf = !HasChildDirectories(folderPath);
-        item.leadingIcon = m_folderIcon;
         m_treeItems.push_back(std::move(item));
 
         const std::vector<std::filesystem::path> childFolders =