Three WATERMARK/FRAME behaviours that share the stamp geometry:
* GPS mark: drag it anywhere on the frame/photo area and pinch it bigger or
smaller. The 0..1 anchor plus the size multiplier ride along in the export
options, so a framed file (whose canvas IS the card/frame) burns the mark in
at exactly the fraction the preview showed.
* The photo's own pinch zoom stays available while the WATERMARK editor is
closed, so a two-finger zoom is never swallowed by the mark while its panel
is open.
* WALL FRAME gains a WALL PORTRAIT / WALL LANDSCAPE chip: the artwork hangs
in its own 4000x3117 orientation instead of the default 90-degree rotation.