test

    DBG_LOG("[PARITY] store gid=" << group_id << " data_len=" << data_len

              << " stripes=" << total_stripes << "\n");

    // Remove old blocks for this group before writing new ones.

    // This prevents orphan stripes when data size changes and avoids

    // unbounded tombstone accumulation in the block store file.

    try {

        remove(group_id);

    } catch (...) {

        // Best-effort: if removal fails, store_stripe will overwrite

        // same-index blocks via tombstone+append anyway.

    }

    // Retry once on failure: stale QUIC connections from a previous operation

    // cause the first stripe to fail; resetting connections fixes it.

    for (int attempt = 0; attempt < 2; ++attempt) {