Socks proxy should support read/write timeouts

[Anthonybelui]

Discussed in https://github.com/encode/httpcore/discussions/859

^{Originally posted by Anthonybelui December 16, 2023} Hello, thanks for developing the library. I wanted to ask you to fix/define the logic for the read timeout in socks_proxy. This creates an infinity reading.

File httpcore/_sync/socks_proxy.py Function _init_socks5_connection() Line: incoming_bytes = stream.read(max_bytes=4096) > incoming_bytes = stream.read(max_bytes=4096, timeout=SomeTimeout)