411f586c67
Follow-up to the try/except guards added in the previous commit. Four sibling call sites all read HERMES_AGENT_TIMEOUT / HERMES_AGENT_TIMEOUT_WARNING / HERMES_AGENT_NOTIFY_INTERVAL via the same read-env-or-fallback pattern, so factor it into _float_env(name, default) alongside the existing _auto_continue_freshness_window() helper.