platform → gfx Relation

File in src/app/platform	Includes file in src/app/gfx
ios / ios_window_backend.mm	backend / metal_renderer.h
iwindow.h	backend / irenderer.h
sdl2_window_backend.cc	resource / arena.h
window.cc	resource / arena.h
window.h	core / bitmap.h
window.h	backend / irenderer.h