Function parent_scroll_offsets 

pub fn parent_scroll_offsets(
    main: &mut World,
    parents: &HashMap<Entity, Entity>,
) -> HashMap<Entity, Vec2>

Returns each entity’s cumulative ancestor-chain ScrollOffset.

• The entity’s own ScrollOffset is excluded; only its descendants translate.
• Returns an empty map when no ScrollOffset components are present.
• Consumed by extract_rects, extract_text, and extract_shadows to subtract the offset from rendered origins.