HiDPI geometry debt from the audit: 15 security-dialog buttons used a raw 40px
height (undersized vs the scaled label at 1.5x), the market "Updated" caption
used a raw SameLine(0,12), and the QR popup's 28px overlay-inset budget wasn't
scaled (wrapping the address at HiDPI). All now go through ui::Layout::dpiScale().
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>