Improve error handling for continue and break

Tried this test case: https://github.com/rust-lang/rust/blob/aa3ca1994904f2e056679fce1f185db8c7ed2703/src/test/ui/closure-array-break-length.rs

#[lang = "fn_once"]
pub trait FnOnce<Args> {
    #[lang = "fn_once_output"]
    type Output;

    extern "rust-call" fn call_once(self, args: Args) -> Self::Output;
}

fn main() {
    |_: [_; continue]| {}; //~ ERROR: `continue` outside of loop

    while |_: [_; continue]| {} {} //~ ERROR: `continue` outside of loop

    while |_: [_; break]| {} {} //~ ERROR: `break` outside of loop
}

We return: https://godbolt.org/z/Ko7o4r5ac

<source>:10:13: error: cannot 'continue' outside of a loop
   10 |     |_: [_; continue]| {}; //~ ERROR: `continue` outside of loop
      |             ^~~~~~~~
<source>:10:13: error: failed to type resolve expression
<source>:12:19: error: expected 'usize' got '!'
   12 |     while |_: [_; continue]| {} {} //~ ERROR: `continue` outside of loop
      |                   ^~~~~~~~
<source>:14:19: error: expected 'usize' got '!'
   14 |     while |_: [_; break]| {} {} //~ ERROR: `break` outside of loop
      |                   ^~~~~
Compiler returned: 1

Start with the referenced test case in src/test/ui/closure-array-break-length.rs and reproduce it in gccrs. Compare the diagnostics for continue and break used in array lengths with the expected errors, ensuring the spurious type-resolution and type-mismatch errors are not emitted.