/**
 * [WHO]: Provides AbortSlot — a single-occupancy holder for an in-flight operation's AbortController
 * [FROM]: No dependencies — wraps the Web AbortController primitive
 * [TO]: Consumed by core/runtime/agent-session.ts (compaction / auto-compaction / branch summary);
 *       reusable by any module that runs one cancellable operation at a time
 * [HERE]: core/platform/abort-slot.ts - generic cancellation primitive (no business knowledge)
 *
 * Replaces the repeated `private _xAbortController: AbortController | undefined` + begin/abort/
 * clear pattern. Holds at most one controller: begin() starts a fresh operation and returns its
 * signal; abort() cancels the active one; clear() releases the slot (call in finally).
 */
export declare class AbortSlot {
    private _controller;
    /** Start a new operation, replacing any prior controller, and return its signal. */
    begin(): AbortSignal;
    /** Whether an operation is currently active. */
    get active(): boolean;
    /** Whether the active operation has been aborted (false when no active operation). */
    get aborted(): boolean;
    /** The active operation's signal, if any. */
    get signal(): AbortSignal | undefined;
    /** Abort the active operation (no-op if none). */
    abort(): void;
    /** Release the slot — call in a finally after the operation settles. */
    clear(): void;
}