add code_point.scl

[ch-yx]

from char to code point & from code point to char

require ~~https://github.com/gnembon/fabric-carpet/pull/1368~~ at least carpet 1.4.82

it provides 3 function: ord, ord_string and chr. ord_string is for string. ord is for char.

and a helper function: string_iter works like built in split with only one argument, but can handle emojis

[ch-yx]

😆 its requirement (https://github.com/gnembon/fabric-carpet/pull/1368) is merged in carpet 1.4.82 😆