/**
 * Data hygiene for ~/.blockrun/.
 *
 * Several files in this directory are written by the @blockrun/llm SDK or
 * by older Franklin versions that didn't ship retention. Without periodic
 * trimming they grow unbounded:
 *
 *   - ~/.blockrun/data/         — every paid API call gets a JSON blob
 *                                 dropped here for forensic replay. SDK
 *                                 has no rotation; verified 5.7 MB across
 *                                 ~2 months of light use, will be 30 MB
 *                                 by year-end and slow `franklin insights`.
 *   - ~/.blockrun/cost_log.jsonl — append-only ledger of every paid call's
 *                                 cost. Same SDK; no rotation.
 *   - brcc-debug.log / brcc-stats.json / 0xcode-stats.json
 *                               — legacy stats / log files from earlier
 *                                 product names. Not written by any
 *                                 current code path.
 *
 * Hygiene runs once per session start (cheap — just stat() + filter +
 * unlinkSync). Best-effort: every operation is wrapped so a single failure
 * never breaks agent boot.
 */
/**
 * Summary of what hygiene removed/trimmed in one pass. Returned so the
 * caller (agent loop) can log it — silent hygiene is hard to verify
 * without poking at disk yourself, which is exactly the kind of thing
 * users shouldn't have to do.
 */
export interface HygieneReport {
    legacyFilesRemoved: number;
    dataFilesTrimmed: number;
    costLogRowsTrimmed: number;
    orphanToolResultsRemoved: number;
}
/**
 * Top-level entry. Call once at agent session start. Catches its own
 * errors so a bad disk never blocks startup. Returns counts so callers
 * can log a one-line summary — verified 2026-05-04 from a real session
 * where hygiene was running silently for hours and there was no way to
 * tell from the log whether anything was being cleaned.
 */
export declare function runDataHygiene(): HygieneReport;
