/**
 * Disk cache of picker labels so listing history does not inspect every
 * session.jsonl.zstd on each launch. Invalidated by file mtime/size.
 */
/** One cached picker row for a stored session. */
export interface SessionIndexEntry {
    id: string;
    label: string;
    updatedAt: number;
    cwd: string;
    hasUserInput: boolean;
    hasReply: boolean;
    unreadable?: boolean;
    mtimeMs: number;
    size: number;
}
/** First page of recent sessions inspected after the header sketch paints. */
export declare const PICKER_PRIORITY_COUNT = 9;
export declare function sessionIndexPath(dshHome?: string): string;
/** Artifact fingerprint used as the cache key. Missing files return zeros. */
export declare function sessionArtifactStat(persistence: object, meta: object): {
    mtimeMs: number;
    size: number;
};
export declare function indexEntryMatchesStat(entry: SessionIndexEntry | undefined, stat: {
    mtimeMs: number;
    size: number;
}): boolean;
export declare function loadSessionIndex(path: string): Promise<Map<string, SessionIndexEntry>>;
export declare function saveSessionIndex(path: string, entries: ReadonlyMap<string, SessionIndexEntry>): Promise<void>;
/** Drop ids that are no longer in the store so the file cannot grow forever. */
export declare function pruneSessionIndex(entries: Map<string, SessionIndexEntry>, keepIds: ReadonlySet<string>): void;