Changes the GraphicsContext to be managed by the GPU core. This eliminates the need for the frontends to fool around with tricky MakeCurrent/DoneCurrent calls that are dependent on the settings (such as async gpu option). This also refactors out the need to use QWidget::fromWindowContainer as that caused issues with focus and input handling. Now we use a regular QWidget and just access the native windowHandle() directly. Another change is removing the debug tool setting in FrameMailbox. Instead of trying to block the frontend until a new frame is ready, the core will now take over presentation and draw directly to the window if the renderer detects that its hooked by NSight or RenderDoc Lastly, since it was in the way, I removed ScopeAcquireWindowContext and replaced it with a simple subclass in GraphicsContext that achieves the same result