[Suxto]

Summary

• Add opt-in mouse and touchpad capture to the native display using Android's public pointer capture API. Volume Down exits capture.
• Handle both Android-translated relative touchpad events and raw touchpad contacts. Apply the touchpad scroll preference independently of physical mouse wheels.
• Track button ownership per input device, preserve motion and button ordering, and drain final releases before closing the input sink.
• Add JVM tests and standalone Android regression probes.

Validation

• Fork CI passed all five static checks and built both Debug and Release APKs.

• 35 focused JVM tests and 17 on-device adapter and regression checks passed on the new branch.

• Windows 11 input was tested on a Xiaomi Pad 8 Pro using the preceding experimental build. The APK from this branch has passed CI and is pending a repeat of that end-to-end hardware test.

• Also verified capture with a USB mouse connected to the Android host.

Related work

#67 also touches pointer capture and mouse event handling in the native display. This PR focuses on touchpad capture, including raw contact fallback, independent scroll direction, and per-device button state. It incorporates the press/release action-button correction for stale button masks. The two changes share integration points in the native display activity.