Function plan 

pub fn plan(
    rows: &str,
    newver: &str,
    launcher: &str,
    o: &Opts,
    e: &dyn Env,
    versions_dir: &str,
    agents: &dyn Fn() -> String,
) -> Plan

Decide what to restart, and say why for everything else.

agents is claude agents --json, fetched by the caller and only when a stale non-pane process actually needs naming: the CLI costs about three seconds to start.