This question evaluates proficiency in C++ template metaprogramming, type traits, SFINAE and Concepts for compile-time callable signature verification, including handling of noexcept, cv/ref qualifiers and implicit conversions.
Implement a C++20 compile-time utility to verify whether a callable matches a target function type. Requirements: create a primary template is_callable_with_signature<Fn, R(Args...)> that yields true if Fn is invocable with Args... and the return type is convertible to R; provide two implementations— (