Generate separete wrappers for multiple PHP versions

[shish]

tl;dr:

1. replace

$function_list = read_docs();
generate_files($function_list, "../generated/");

with

foreach(["8.1", "8.2", "8.3", "8.4"] as $version) {
    exec("cd docs && git checkout $version");
    $function_list = read_docs();
    generate_files($function_list, "../generated/$version/");
}

2. generate a bunch of stubs like generated/misc.php:

<?php
if(PHP_VERSION == "8.1") require_once __DIR__ . "/8.1/misc.php";
if(PHP_VERSION == "8.2") require_once __DIR__ . "/8.2/misc.php";
if(PHP_VERSION == "8.3") require_once __DIR__ . "/8.3/misc.php";
if(PHP_VERSION == "8.4") require_once __DIR__ . "/8.4/misc.php";

Currently the Exceptions are shared between all versions, which I think is a good idea?

This isn't even remotely tested, just a proof of concept to show what this kind of approach might look like