Support scalar container variables for factory functions

[clue]

This changeset adds support for scalar variables in the container configuration for all factory functions:

<?php

require __DIR__ . '/../vendor/autoload.php';

$container = new FrameworkX\Container([
    Acme\Todo\UserController::class => function (bool $debug, string $hostname) {
        // example UserController class requires two scalar arguments
        return new Acme\Todo\UserController($debug, $hostname);
    },
    'debug' => false,
    'hostname' => fn(): string => gethostname()
]);

// …

The previous version only supported string values, we now support all scalar values (string, int, float, bool). This is the next step in adding better configuration support and support for environment variables and .env (dotenv) files as discussed in #101.

Builds on top of #178, #163, #97, #95 and others