The length value in millimeters to format.
Determines whether to format the output in imperial units (feet/inches) or metric units.
Optionalnegative: boolean = falseOptional flag indicating if the length should be prefixed with a negative sign.
formatLength(1000, false) returns "1 m"formatLength(304.8, true) returns "1'" (1 foot in imperial)formatLength(-1234, false, true) returns "- 1.234 m"
Formats a length value into a human-readable string, either in metric or imperial units.