Implement GX Thread for Asynchronous Rendering

- Introduced a new GX thread to handle the rendering pipeline, allowing the game thread to post commands without blocking.
- Added `gx_thread.h` and `gx_thread.cpp` to manage the command ring buffer and thread synchronization.
- Updated `vi.cpp` to utilize the GX thread for rendering tasks, improving frame pacing and responsiveness.
- Modified `main.cpp` to configure and start the GX thread, ensuring it integrates with the existing rendering workflow.
- Enhanced `openxr_integration.cpp` to register the GX thread with OpenXR for better performance in VR scenarios.
- Refactored `settings_overlay.cpp` to remove unnecessary waits for the frame worker, as the overlay now draws directly into the game thread's ImGui frame.
- Improved error handling and logging in the GX thread to capture exceptions during command execution.

aurora-main/include/aurora/aurora.h

@@ -218,6 +218,17 @@ void aurora_end_frame();
 // Seal the current frame with an opaque application safety tag. Aurora rejects
 // an immersive provider packet unless its contentTag matches this exact frame.
 void aurora_end_frame_tagged(uint64_t contentTag);
+// aurora_end_frame_tagged() plus the host-owned ImGui frame to present with it (the handle from
+// aurora_imgui_host_frame_end(), which this call consumes; NULL presents no host ImGui frame).
+void aurora_end_frame_ex(uint64_t contentTag, void* imguiFrame);
+// When the host pumps SDL events itself (aurora_update() on the window's thread) and drives
+// begin/end frame from another thread, this stops those calls from pumping events.
+void aurora_set_host_event_pump(bool hostPumps);
+typedef void (*AuroraFrameLogCallback)(char* buffer, uint32_t bufferSize, double windowSeconds,
+                                       uint32_t frames);
+// Called with each five-second frame-rate log window (where that log is enabled); a non-empty
+// buffer is logged as one extra line.
+void aurora_set_frame_log_callback(AuroraFrameLogCallback callback);
 /**
  * Relocates the immersive camera for the frame about to be sealed.
  *