Function styled_progress_bar 

pub fn styled_progress_bar(total: u64, unit_label: &str) -> ProgressBar

Shared bar used by every par-over-column visitor so progress shows the workspace-standard [elapsed] bar pos/len (eta) <unit_label> style across random projection, collapsing, and downstream column scans. Delegates to the canonical legume_numeric::matrix::progress::new_progress_bar (single style, single MULTI_PROGRESS) and keeps the 500 ms steady tick so the bar animates even when a single block is slow. Exported so downstream crates (data_beans::alg, senna) can reuse the same look.