Update to support Godot4.x

[BThacker]

Various changes:

@tool vs tool @export vs export

timer init and creation

to_utf8 > to_utf8_buffer

listen > bind

is_listening > is_bound

poolbytearray > packedbytearray

[BThacker]

Converted to draft, getting weird behavior when the session is created but it takes a few moments for the client to connect. Packets sent back to the host computer arent' received. Maybe a keep alive of some sort sent to the STUN server is required? I will experiment.