pub fn try_service_name(app_id: &str) -> Result<String, InvalidAppId>Expand description
The service name arbitration hosts for app_id: the normalised id plus -shell,
so an id that is already [a-z0-9-] gives exactly <id>-shell (running instances keep being
found across upgrades) and "app.mailright" gives "app-mailright-shell". rightkit-daemon
allows only 1 to 48 bytes of [a-z0-9-], so an empty id or one longer than 42 bytes is refused.