term: Color Node IDs — heartwood

Though Node IDs technically are not hashes, we can use similar techniques to “fingerprint” them.

This seems to break tables.

See also:

 /// Format a node id to be more compact.
 pub fn node(node: &NodeId) -> Paint<String> {
     const CHARS_PER_BLOCK: usize = 7;
     const BYTES_PER_CHAR: usize = 3;
     let pk = node.0;
     let node = node.to_human();
     let start = node.chars().take(7).collect::<String>();
     let end = node.chars().skip(node.len() - 7).collect::<String>();
     fn colored_char(r: u8, g: u8, b: u8, c: char) -> String {
         let fg = term::Color::RGB(r, g, b);
         format!(
             "{}",
             Paint::from(c).fg(fg).bg(fg
                 .complimentary()
                 .expect("RGB color has complimentary color"))
         )
     }
     let start = pk
         .windows(BYTES_PER_CHAR)
         .zip(node.chars().take(CHARS_PER_BLOCK))
         .map(|(b, c)| colored_char(b[0], b[1], b[2], c))
         .collect::<String>();
     let end = pk
         .windows(BYTES_PER_CHAR)
         .rev()
         .zip(node.chars().skip(node.len() - CHARS_PER_BLOCK))
         .map(|(b, c)| colored_char(b[0], b[1], b[2], c))
         .collect::<String>();
     Paint::new(format!("{start}…{end}"))
 }

         Style::new(self)
     }
     pub fn complimentary(&self) -> Option<Color> {
         match *self {
             Color::Unset => Some(Color::Unset),
             Color::White => Some(Color::Black),
             Color::RGB(r, g, b) => Some(Color::RGB(u8::MAX - r, u8::MAX - g, u8::MAX - b)),
             _ => None,
         }
     }
     pub(crate) fn ansi_fmt(&self, f: &mut dyn fmt::Write) -> fmt::Result {
         match *self {
             Color::Unset => Ok(()),