Fix HWND resize timing issue
Fix HWND resize timing issue

* There was a race condition where the newly created HWND surface could
  be resized during swap chain creation. This causes a
  `VK_ERROR_DEVICE_LOST`, but is very timing dependent.
* The fix was to finish the resize, via `ResourcePreview::setActive()` /
  `QWidget::show()` before scheduling any async functions that could
  create a swapchain, namely `IReplayOutput::AddThumbnail()`.

Zorro666/renderdoc,Zorro666/renderdoc,Zorro666/renderdoc,Zorro666/renderdoc,baldurk/renderdoc,Zorro666/renderdoc,baldurk/renderdoc,baldurk/renderdoc,baldurk/renderdoc,baldurk/renderdoc,Zorro666/renderdoc,baldurk/renderdoc