Fix: Shift+Wheel scrolls horizontally instead of vertically

[Copilot]

Some browsers (e.g. Yandex on Windows 11) dispatch WheelEvent with deltaY/shiftKey=true and deltaX=0 for Shift+Wheel, expecting the app to handle the axis conversion. RevoGrid was consuming deltaY vertically and then bailing out of the horizontal handler — resulting in vertical scroll until hitting the bottom, at which point native horizontal scroll took over.

Changes

src/components/scroll/revogr-viewport-scroll.tsx

• Added shiftKey?: boolean to LocalScrollEvent
• onVerticalMouseWheel: bail out early when shiftKey is set — let the horizontal handler own it
• onHorizontalMouseWheel: compute effectiveDelta from deltaX if available, otherwise fall back to deltaY when shiftKey is held

// Before
if (!e.deltaX) return;

// After — Shift+Wheel with deltaY-only browsers now scrolls horizontally
const effectiveDelta = e.deltaX !== 0 ? e.deltaX : (e.shiftKey ? e.deltaY : 0);
if (!effectiveDelta) return;

e2e/scroll.spec.ts (new)

• Asserts Shift+Wheel advances scrollLeft and leaves scrollTop unchanged
• Asserts normal Wheel advances scrollTop and leaves scrollLeft unchanged

[sonarqubecloud]

Quality Gate passed

Issues
2 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud