Function solana_runtime::snapshot_utils::create_snapshot_meta_files_for_unarchived_snapshot

fn create_snapshot_meta_files_for_unarchived_snapshot(
    unpack_dir: impl AsRef<Path>
) -> Result<()>

BankSnapshotInfo::new_from_dir() requires a few meta files to accept a snapshot dir as a valid one. A dir unpacked from an archive lacks these files. Fill them here to allow new_from_dir() checks to pass. These checks are not needed for unpacked dirs, but it is not clean to add another flag to new_from_dir() to skip them.