feat(fuzz): Add experimental comptime code generator

[rkarabut]

Description

Printing noir_ast_fuzzer as Noir, we should make it possible to fuzz comptime output against that of the equivalent compiled code. This adds an experimental version of valid comptime code generator, building a comptime function and wrapping its call with appropriate literal arguments in a comptime block within main .

Example of running cargo run -p noir_ast_fuzzer --example sample_comptime:

fn main() -> pub Field {
    comptime {
        func_1(18278151528840398125126511725758739340)
    }
}
comptime fn func_1(a: Field) -> Field {
    let b = if true {
        for idx_c in 1637873142 .. 1637873144 {
            let mut d = false;
            d = d;
            d = {
                d = d;
                d = (4163569491 < 2148799602);
                if (!false) {
                    for idx_e in -6940455744395345574 .. -6940455744395345566 {
                        if d {
                            ()
                        };
                        let f = (2544915962152465123 < -1838314094939617270);
                    };
                    ((idx_c as u128) <= 20225268882629477752056013539620857730)
                } else {
                    d
                }
            };
            d = d;
        };
        (a, a)
    } else {
        (-80171648342934597222692573068578438886, (-a))
    };
    a
}

Problem*

Summary*

Additional Context

Documentation*

Check one:

• No documentation needed.
• Documentation included in this PR.
• [For Experimental Features] Documentation to be submitted in a separate PR.

PR Checklist*

• I have tested the changes locally.
• I have formatted the changes with Prettier and/or cargo fmt on default settings.

[aakoshh]

Cool, happy fuzzing!