Lightroom-style 'Screen' output sharpen (unsharp mask, 3x3 convolution
via Skia ImageFilter.MakeMatrixConvolution, amount 0.5, kernel sums to
1) applied to final pixels before JPEG encode. Camera-capture branch
passes { dpi: 300, sharpen: true }; library-mode export untouched.
Export pixels were already full resolution - sharpen is a new final
GPU pass, no pixel-count change.
Skia JPEG re-encode drops original header (72dpi camera default). New
src/utils/jpegDpi.ts rewrites JFIF APP0 density + EXIF X/YResolution
(endian-aware) or inserts minimal JFIF when neither exists; applied via
processAndExportPhoto options.dpi in the camera-capture branch only.
Library-mode exports untouched. Pixels never change - metadata only.
3dtours