fix: SG-41698: Add Alt modifier check for mouse wheel events

[tjjackson]

Linked issues

Summarize your change.

Added a check for Alt modifier to QTTranslator::sendMouseWheelEvent()

Describe the reason for the change.

The Alt key combined with the mouse wheel triggers horizontal scrolling, and will be reported in angleDelta().x() instead of angleDelta().y(). I added a check for the Alt modifier for whether to use angleDelta().x() or angleDelta().y() as the delta for determining if the wheel is moving down or up.

Describe what you have tested and on which operating system.

Successfully tested on Rocky Linux 9.5

Add a list of changes, and note any that might need special attention during the review.

If possible, provide screenshots.

[bernie-laberge]

Thank you @tjjackson !

[eloisebrosseau]

@tjjackson I think you forgot to format your code. You can use pre-commit like mentioned in the documentation. To manually trigger it, you can run pre-commit run clang-format --all-files and commit the fix

[bernie-laberge]

Sorry @tjjackson, the formatting error was my bad: the formatter hadn't ran on the code I proposed to you because I never committed it.
After installing the pre-commit:
pre-commit install
The pre-commit run clang-format --all-files should format the it correctly : it should remove the extra space after the horizontalModifier =.
Thanks !

[tjjackson]

Yeah I copied-pasted it and didn't think to run pre-commit again, should be good now

[Copilot]

Pull request overview

This PR updates OpenRV’s Qt event translation so mouse wheel “up/down” direction is derived from the correct QWheelEvent::angleDelta() axis when a horizontal-scroll modifier is pressed (Alt on Linux/Windows, Shift on macOS).

Changes:

• Add platform-specific modifier selection to detect horizontal scrolling for wheel events.
• Use angleDelta().x() instead of angleDelta().y() when the horizontal-scroll modifier is active.

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