macOS Tao: trackpad scroll magnitude includes display scale unlike AWT

[sargunv]

🐛 Describe the bug

On macOS, Tao and AWT report different trackpad scroll magnitudes to the same Compose content. This is separate from the horizontal sign issue in #652.

⚠️ Current behavior

We observed different trackpad pan speeds while testing maplibre/maplibre-compose#1290. Source inspection shows a difference in how display scale enters the scroll conversion:

• OpenJDK uses scrollingDelta * 0.1, without a display-scale multiplier.
• Tao converts logical AppKit deltas into physical pixels. TaoWindow then divides them by 10.
• The popup conversion in MacOsWheelDelta.kt also includes display scale.

For a 10-point AppKit delta on a 2× display, these conversions predict an absolute Compose scroll delta of 1 under AWT and 2 under Tao. They predict matching magnitudes on a 1× display. This ratio is derived from source, not a recorded comparison of identical physical gestures.

✅ Expected behavior

The same Compose scroll handling should produce the same movement under AWT and Tao, independent of display scale. AWT is the reference for the AWT-compatible scroll units Nucleus exposes.

💣 Steps to reproduce

1. Observe PointerEventType.Scroll and change.scrollDelta in identical AWT and Tao Compose content on a Retina display.
2. Compare vertical trackpad scrolling, which avoids the separate horizontal sign issue in macOS Tao: horizontal trackpad scrolling is reversed relative to AWT #652.
3. Repeat on a 1× display to compare the effect of display scale.

📷 Screenshots

None; this concerns input deltas.

📱 Tech info

• Device: macOS desktop with a trackpad and Retina display.
• OS: macOS.
• Library/App version: Nucleus 2.5.12, Compose Multiplatform 1.12.0, OpenJDK 25.