fn pick_l1_overlap_only(
sorted_runs: Vec<SortedRun<FileHandle>>,
max_output_file_size: Option<u64>,
mapper: &PrimaryKeyRangeMapper,
) -> Vec<FileHandle>fn pick_l1_overlap_only(
sorted_runs: Vec<SortedRun<FileHandle>>,
max_output_file_size: Option<u64>,
mapper: &PrimaryKeyRangeMapper,
) -> Vec<FileHandle>