Function actionable_init_error 

pub fn actionable_init_error(model_id: &str, source: impl Display) -> String

Build a startup error message that tells the user how to escape. The wrapped error from ModelFactory::create already explains WHAT failed (auth, 404, network); this wrapper appends WHAT TO DO so a user with a stale or unauthenticated last_used_model doesn’t have to dig through docs to recover. Used by both startup paths (interactive Orchestrator::run + non-interactive run_non_interactive in main.rs).