(py) set_cookies() .unwrap() panics across FFI on a malformed server Set-Cookie

[barjin]

🤖 Found by Claude ultrareview — automated high-effort code review. Please verify independently before acting.

Location: impit-python/src/cookies.rs:94 (set_cookies)

The Python cookie-constructor and set_cookie calls are .unwrap()ed:

let py_cookie = self.cookie_constructor.call(py, (), Some(&kwargs)).unwrap();
let args = PyTuple::new(py, vec![py_cookie]).unwrap();
self.cookie_jar.call_method1(py, "set_cookie", args).unwrap();

This runs inside reqwest's cookie-store callback during response handling — a Rust callback driven by the HTTP stack.

Impact: a hostile server's malformed Set-Cookie (e.g. a bad domain/expiry that http.cookiejar.Cookie rejects), or a custom cookie jar whose set_cookie raises, panics inside the callback and unwinds across the FFI boundary — an abort rather than a catchable Python exception. A crafted server response can therefore crash the host process. Note the neighboring set_item calls already use .unwrap_or_default().

Suggested direction: convert these .unwrap()s into propagated errors (or at minimum skip the offending cookie) so a malformed Set-Cookie cannot abort the process.