merge master changes

src/xrt/compositor/client/comp_gl_client.c

src/xrt/compositor/client/comp_vk_client.c

src/xrt/include/xrt/xrt_compositor.h

src/xrt/include/xrt/xrt_defines.h

src/xrt/include/xrt/xrt_instance.h

src/xrt/ipc/CMakeLists.txt

src/xrt/ipc/ipc_client_compositor.c

src/xrt/ipc/ipc_client_instance.c

src/xrt/ipc/ipc_protocol.h

src/xrt/ipc/ipc_server.h

src/xrt/ipc/ipc_server_client.c

src/xrt/ipc/ipc_server_process.c

src/xrt/ipc/proto.json

src/xrt/ipc/proto.py

src/xrt/state_trackers/gui/gui_prober.c

src/xrt/state_trackers/oxr/oxr_event.c

src/xrt/state_trackers/oxr/oxr_extension_support.h

src/xrt/state_trackers/oxr/oxr_instance.c

src/xrt/state_trackers/oxr/oxr_objects.h

src/xrt/state_trackers/oxr/oxr_session.c