Function request_wants_keep_alive 

pub fn request_wants_keep_alive(req: &HttpRequest) -> bool

Whether the server should keep the connection open after answering req — THE ONE keep-alive law both execution tiers (the interpreter’s serve loop and the AOT serve_on) apply, so their Connection: responses can never drift: HTTP/1.1 connections persist unless the client’s Connection header token list contains close (case-insensitive).

Scope note: parse_request does not retain the version token (it accepts any HTTP/*), so HTTP/1.0’s implicit-close default is not modeled — every parsed request gets HTTP/1.1 persistence semantics.