fix: D3D12 screenshot implementation and tests

engine/src/RHI/D3D12/D3D12CommandQueue.cpp

@@ -73,11 +73,23 @@ uint64_t D3D12CommandQueue::GetCompletedValue() {
 }
 
 void D3D12CommandQueue::WaitForIdle() {
-    ID3D12Fence* fence = nullptr;
-    HRESULT hResult = m_commandQueue->GetDevice(IID_PPV_ARGS(&fence));
-    if (SUCCEEDED(hResult)) {
-        m_commandQueue->Wait(fence, UINT64_MAX);
-        fence->Release();
+    // Get the device from the command queue
+    ID3D12Device* device = nullptr;
+    HRESULT hr = m_commandQueue->GetDevice(IID_PPV_ARGS(&device));
+    if (SUCCEEDED(hr)) {
+        // Create a fence to signal when queue is idle
+        ID3D12Fence* fence = nullptr;
+        hr = device->CreateFence(0, D3D12_FENCE_FLAG_NONE, IID_PPV_ARGS(&fence));
+        if (SUCCEEDED(hr)) {
+            // Signal the fence
+            m_commandQueue->Signal(fence, 1);
+            // Wait for it to complete
+            while (fence->GetCompletedValue() < 1) {
+                Sleep(1);
+            }
+            fence->Release();
+        }
+        device->Release();
     }
 }