/** `ztrack issue list --actionable|--blocked` — returns true once handled (whether it succeeded,
 *  errored, or degraded), so the caller never falls through to the generic backend dispatch. Returns
 *  false for a plain `issue list` (no frontier flag) — that keeps flowing through the existing path,
 *  byte-identical. */
export declare function handleIssueListFrontier(args: string[]): Promise<boolean>;