Method cleanup

packages/utils/src/lib/wal-sharded.ts:398–414

* Cleanup shard files by removing them from disk. * Coordinator-only: throws error if not coordinator to prevent race conditions. * Idempotent: returns early if already cleaned.

()

   * Idempotent: returns early if already cleaned.
   */
  cleanup() {
    if (!this.isCoordinator()) {
      throw new Error('cleanup() can only be called by coordinator');
    }

    if (this.#state === 'cleaned') {
      return;
    }

    this.shardFiles()
      .filter(f => fs.existsSync(f))
      .forEach(f => {
        fs.unlinkSync(f);
      });

    this.#state = 'cleaned';
  }

  get stats() {
    // When finalized, count all shard files from filesystem (for multi-process scenarios)