Module duration 

Human-readable Duration formatting for the per-task summary lines and the run-level epilogue.

The grammar picks the two coarsest magnitudes that fit:

Duration	Rendered as
< 1s	176ms
< 1m	7s 856ms
< 1h	1m 23s
>= 1h	1h 23m

Sub-millisecond durations round to the nearest millisecond (clamping at 1ms so a sub-millisecond run does not display as 0ms). The grammar deliberately drops fractional digits; readers want order-of-magnitude information, not microsecond precision.

Functions

format_duration

Render duration in the grammar described at the module level. Allocates a single String.