Function draw_pin_placeholders 

pub fn draw_pin_placeholders(
    bbox: Rect,
    pin: &Pin,
    painter: &mut Style<'_, impl Renderer>,
)

Draw the faint “Add Name”/“Add Type”/“+tag” prompts for one block pin’s empty label slots — used by the selected-block render so empty fields are discoverable. The “+tag” prompt is only drawn for a shown (not hidden) tag.