Derive Macro FdlArgs 

#[derive(FdlArgs)]
{
    // Attributes available to this derive:
    #[option]
    #[arg]
}

Derive macro for FdlArgs. Generates argv parsing, --fdl-schema emission, and --help rendering from a single struct definition. Derive FdlArgs on a struct with named fields to generate an argv parser, --fdl-schema JSON emitter, and ANSI-coloured --help renderer. See the crate-level docs for the attribute reference and a worked example.