Derive Macro CodeMode 

#[derive(CodeMode)]
{
    // Attributes available to this derive:
    #[code_mode]
}

Derive macro that generates register_code_mode_tools for Code Mode servers.

Requires a named struct with four well-known fields: code_mode_config, token_secret, policy_evaluator, code_executor.

See crate-level documentation for the full field name convention.