public async Task <IActionResult> RegisterAsync([FromBody] UserRegisterDto registerDto)
        {
            if (ModelState.IsValid)
            {
                var result = await _korisnikService.RegisterUserAsync(registerDto);

                if (result.IsSuccess)
                {
                    return(Ok(result)); // Status code 200
                }
                return(BadRequest(result));
            }
            return(BadRequest("Provjerite ponovno upisane podatke.")); // Status code 400
        }