Soft proof is per-pixel, so the After window carries the proof like the
whole-frame render under it (the proof key is part of the tile's look).
New tests: a 1:1 window of a 24 MP photo equals the full-size export to
within one level; soft proofing at 1:1 is a canvas-sized frame plus a
native window. profile_slider_drag gains a soft-proof case. Gap 4 closed,
checklist row to done with measured Linux latencies.
Sources: own design.
Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>
