Function derive_session_name 

pub fn derive_session_name(prompt: &str) -> String

Derive a display name from the resolved prompt for claude --name. Shows up in the claude --resume picker, the terminal title, and the prompt box. Without it, sessions roba creates are effectively invisible to the picker.

Shape: roba: <first 40 chars of the first non-empty line>. The roba: prefix makes sessions distinguishable from interactive Claude Code sessions in the same project’s history.