Fix type hints

[Athari]

Consider replacing the current mess of types with what seems to be the current meta:

• callable
• iterable (Add iterable to allowed input parameters for from() #49)

Note PHP version restrictions:

• <scalar> = 7.0+
• ?A = 7.1+
• A|B = 8.0+
• A&B = 8.1+
• A&B|C = 8.2+

This probably matches the current plan to restrict YaLinqo 4.0 to PHP 8.0+, but maybe we need to go further.

Non-shitty properties of PHP 8.4 and non-shitty class constants of PHP 8.3 sound tasty, but users will probably get angry about PHP 8.4+ restriction just for minor cleanup of the code.