Upgrade project asset watcher to native Win32 notifications

editor/src/Core/ProjectAssetWatcher.h

@@ -2,9 +2,12 @@
 
 #include "Core/IEditorContext.h"
 
+#include <atomic>
 #include <cstdint>
 #include <filesystem>
+#include <mutex>
 #include <string>
+#include <thread>
 #include <unordered_map>
 
 namespace XCEngine {
@@ -12,6 +15,8 @@ namespace Editor {
 
 class ProjectAssetWatcher {
 public:
+    ~ProjectAssetWatcher();
+
     void Attach(const std::string& projectPath);
     void Detach();
     void Update(IEditorContext& context, float dt);
@@ -54,6 +59,11 @@ private:
     using Snapshot = std::unordered_map<std::string, AssetEntryState>;
 
     void RefreshProjectBinding(const std::string& projectPath);
+    void StartNativeWatcher();
+    void StopNativeWatcher();
+    void RunNativeWatcher(void* directoryHandle, std::filesystem::path watchedRoot);
+    void ConsumeNativeChanges();
+    void ScheduleRefresh(const ChangeStats& changes);
     void ScanForChanges();
     void FlushPendingRefresh(IEditorContext& context);
     static void BuildSnapshot(const std::filesystem::path& assetsRoot, Snapshot& outSnapshot);
@@ -64,8 +74,15 @@ private:
     Snapshot m_snapshot;
     ChangeStats m_pendingChanges;
     float m_scanCooldownSeconds = 0.0f;
+    float m_nativeRestartCooldownSeconds = 0.0f;
     float m_debounceSeconds = 0.0f;
     bool m_hasPendingRefresh = false;
+    std::thread m_nativeWatcherThread;
+    std::mutex m_nativeChangeMutex;
+    ChangeStats m_threadPendingChanges;
+    std::atomic<bool> m_nativeWatcherHealthy{false};
+    std::atomic<bool> m_pollingResyncRequested{false};
+    void* m_nativeStopEvent = nullptr;
 };
 
 } // namespace Editor