Function draw_size_readout 

pub fn draw_size_readout(
    bbox: Rect,
    painter: &mut Style<'_, impl Renderer>,
) -> Rect

Draw a block’s size in grid cells inside its upper-left corner, where the pin gutter above the first slot leaves the one interior region no label occupies. Shown only while the block is being resized, on the rect the drop will commit. Returns the drawn extent.