/**
 * ProcessTracker singleton for zombie prevention.
 *
 * Maintains a set of all active subprocess PIDs and their metadata.
 * On Node.js exit, all tracked processes are forcefully terminated.
 *
 * Per spec §6.4: handlers are installed once, on first register() call.
 */
export interface ProcessTracker {
    /** Register a spawned process. Called by RunHandle during spawn. */
    register(pid: number, groupId: number, runId: string): void;
    /** Unregister a process after it exits. Called on process exit. */
    unregister(pid: number): void;
    /** Kill all tracked processes. Sends SIGTERM then SIGKILL after grace period. */
    killAll(): void;
    /** Number of currently tracked processes. */
    readonly activeCount: number;
}
/** Global ProcessTracker singleton. */
export declare const processTracker: ProcessTracker;