Function draw_nearest_anchor_target 

pub(crate) fn draw_nearest_anchor_target<C: Canvas>(
    data: &Drawing<'_>,
    pointer: Pos2,
    exclude: Option<PinId>,
    painter: &mut Style<'_, C>,
) -> Option<(PinId, Pos2)>

Draw the grow-out target on the anchor nearest pointer (skipping exclude), returning it if one is in range. Shared by the select tool’s route-start and the route tool’s hover/end targets so they animate identically.