Function format_latency_us 

pub fn format_latency_us(us: i64) -> String

Format a latency value in microseconds for human-readable display.

Three display tiers:

• < 1ms (< 1,000μs): "142μs"
• 1ms..1s (1,000..1,000,000μs): "4.20ms" (two decimal places)
• ≥ 1s (≥ 1,000,000μs): "1,234ms" (comma-separated, no decimals)

Examples

use mcpr_core::time::format_latency_us;

assert_eq!(format_latency_us(200), "200μs");
assert_eq!(format_latency_us(4_200), "4.20ms");
assert_eq!(format_latency_us(1_500_000), "1,500ms");