Function group_chrome 

pub fn group_chrome(n: usize) -> String

Comma-group a count for the application’s own chrome — the control bar’s row count, info-panel totals, and similar labels.

Deliberately unconditional: these are datui’s labels, not the user’s data, so they stay readable regardless of display.number_format or the , toggle. Keeping the distinction means turning formatting off to read exact data values never makes the surrounding UI harder to read.