Function apply_a11y_scroll_into_view 

pub fn apply_a11y_scroll_into_view(
    requests: ResMut<'_, A11yScrollIntoViewRequests>,
    parents: Query<'_, '_, &ChildOf>,
    transforms: Query<'_, '_, &Transform>,
    scrolls: Query<'_, '_, (&Transform, &mut Scroll, &mut ScrollOffset)>,
)

W5.3 consumer for inbound Action::ScrollIntoView AccessKit actions.

• Drains lumen_core::components::A11yScrollIntoViewRequests each tick. For every requested entity, walks the [ChildOf] chain up to the nearest ancestor that carries Scroll + ScrollOffset and updates the offset so the target’s bounding box sits inside the container’s viewport rect.
• Vertical-axis containers move the offset along Y, horizontal along X, Both along both axes simultaneously.
• When the target is already fully visible, the offset is left untouched (idempotent - repeated requests don’t drift).
• Velocity on the target axis is zeroed so a previously-fired inertial fling does not immediately scroll back away from the focused element.
• The actual clamp to [0, content - viewport] is left to clamp_scroll_offsets which runs in TickStage::A11ySync after this system.