The status line is the toast that clears itself after 5 s, so the
preparing notice went blank while the viewer was still on the CPU for the
rest of a cold-cache build (tens of seconds), though `init_gpu` says the
status bar tells the user so. draw_toast now leaves that one status up
while `gpu_initializing()`; `finish_gpu_build` clears it when the
compositor lands, and the worker's repaint brings that frame, so the
toast doesn't tick meanwhile. A click still dismisses it; every other
status clears as before.
Test: with the build held on its gate, 30 more steps (7.5 s) leave the
status as it was; before this change it was empty by then.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>