Add examples / alternative docs using Python 3.12 PEP 695

[SimonHeybrock]

Example:

type mylist[T] = list[T]
type mydict[V] = dict[str, V]

import sciline as sl

def make_int_list() -> mylist[int]:
    return [1, 2, 3]

def make_str_list() -> mylist[str]:
    return ['a', 'b', 'c']

def f[T](x: mylist[T]) -> mydict[T]:
    return {f'{x}': x}

pl = sl.Pipeline([f, make_int_list, make_str_list])
pl.get(mydict[int]).compute()

This is much cleaner than the sciline.Scope helper and the use of NewType.

Note that mypy might still not support this (fully).

[YooSunYoung]

Looks really neat!
Does it imply that we can only use python 3.12 for docs build?

[SimonHeybrock]

Does it imply that we can only use python 3.12 for docs build?

Yes, I think so.