When fish crashes due to a panic, the terminal window is closed. Some
terminals keep the window around when the crash is due to a fatal signal,
but today we don't exit via fatal signal on panic.
There is the option to set «panic = "abort"» in Cargo.toml, which
would give us coredumps but also worse stacktraces on stderr.
More importantly it means that we don't unwind, so destructors are skipped
I don't think we want that because we should use destructors to
restore the terminal state.
On crash in interactive fish, read one more line before exiting, so the
stack trace is always visible.
In future, we should move this "read one line before exiting" logic to where
we call "panic!", so I can attach a debugger and see the stacktrace.
The incompatible_msrv one is a false positive because we have polyfills for
is_some_and() and is_ok_or() which are Rust 1.74. I'm not yet sure how to
communicate that to Clippy.