shownMs
A span's time, as tcm traces shows it.
export function shownMs(ms: number): string { if (ms < 1) return `${ms.toFixed(2)}ms`; if (ms < 10) return `${ms.toFixed(1)}ms`; if (ms < 1000) return `${Math.round(ms)}ms`; return `${(ms / 1000).toFixed(ms < 10_000 ? 2 : 1)}s`; }