Function format_holder_list 

pub fn format_holder_list(holders: &[HolderInfo]) -> String

Format a HolderInfo slice for inclusion in user-facing error strings. Empty slice yields the NO_HOLDERS_RECORDED sentinel so the diagnostic is unambiguous — a stale lockfile whose holder has exited presents as empty, and the error should say so rather than print a misleading blank. Non-empty renders one pid={pid} cmd={cmdline} line per holder, newline-separated and indented two spaces, so a multi-holder error stays readable when embedded in a wrapping anyhow chain; the prior comma-joined form ran every holder into a single wide line that terminals wrapped arbitrarily mid-cmdline.