highlighted_hash grows a width budget - shorter than the key shows an
ellipsis, shorter keys pad so lanes align - making it THE hash widget.
The chat sender palette moves to theme.name_style as the app-wide node
name colour rule; our own node is always the pure-white "you" style
(the nodes table's self row now follows it).
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>