Function thread_wants_an_answer 

pub fn thread_wants_an_answer(
    thread: &RawThread,
    viewer: &str,
    seen: &Answered,
) -> bool

Whether a thread still wants an answer.

Three tests, and each catches something the others do not:

• Somebody other than the viewer wrote the newest live message in it. Answering yourself does not terminate.
• GitHub does not already say it is resolved. Authoritative, shared between machines, and free.
• It has moved since spar last answered. This is the one that matters most, and it exists because of a deliberate decision elsewhere: spar leaves a thread it disagreed with open, for the person who raised it. Unresolved alone would therefore make spar re-argue every point it lost, once per run, forever.