highlighted_hash lit a key's path-hash prefix in the fixed brand cyan;
it now takes the node's hash-derived palette hue — the same colour the
node's name wears — so a hash carries its node's identity colour even
where no name is known, and a key's prefix, its name, and its map
labels all agree. The remainder (and a hash standing in as a name)
stays muted, and the truncation ellipsis keeps inheriting the colour
of the digit it replaces.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>