fmt/bytes `format()` should use non-breaking space between the number and the unit

[lionel-rowe]

Is your feature request related to a problem? Please describe.

fmt/bytes format() should use non-breaking space between the number and the unit.

https://en.wikipedia.org/wiki/Non-breaking_space#Non-breaking_behavior

For example, if the text "100 km" will not quite fit at the end of a line, the software may break the line between "100" and "km". Using a non-breaking space between "100" and "km" will prevent this behaviour. This guarantees that the text "100 km" will not be broken—if it does not fit at the end of a line, it is moved in its entirety to the next line. For this reason, many style guides recommend using a non-breaking space between numbers and their associated units.[4][5]

Describe the solution you'd like

Use \xa0 non-breaking space instead of \x20 space between number and units in fmt/bytes:

import { format } from '@std/fmt/bytes'
import { assertEquals } from '@std/assert'
assertEquals(format(1e6), '1\xa0MB')

Describe alternatives you've considered

N/A

[lionel-rowe]

This might be the wrong fix where the locale option is set, as (1).toLocaleString('en', { style: 'unit', unit: 'kilobyte' }) uses a normal space (it should probably use NBSP really, but that would need to be fixed upstream in CLDR). Actually, delegating more of the logic to toLocaleString would probably be worthwhile where locale is used, as format(1, { locale: 'fr' }) currently gives "1 B", whereas (1).toLocaleString('fr', { style: 'unit', unit: 'byte' }) gives "1 o" ("octet")