fn localize_mesh_batch(rb: &RecordBatch) -> Option<RecordBatch>Expand description
Re-base a mesh-table row group’s vertex_start / index_start columns
from whole-model globals back to batch-local zero, by subtracting the
group’s own first-row values — the exact base offset
StreamingParquetCacheWriter::append fed into build_mesh_tables for that
batch. Every other column is untouched. Columns are resolved BY NAME, so a
schema reorder can never silently re-base the wrong one.