Function generate_docs 

pub fn generate_docs(
    module_names: &Option<Vec<String>>,
    files: &Option<Vec<(String, String)>>,
    format: &DocFormat,
    include_builtin: bool,
) -> Result<String, Error>

Generate documentation for mq functions, macros, and selectors.

If module_names or files is provided, only the specified modules/files are loaded. Both can be combined. If include_builtin is true, built-in functions are also included. Otherwise, all builtin functions are documented.