Create typed input helpers for common cases
Usage
input_string(name, description = NULL, ...)
input_number(name, description = NULL, ...)
input_boolean(name, description = NULL, ...)
input_integer(name, description = NULL, ...)
input_enum(name, values, description = NULL, ...)
input_array(name, item_type = ellmer::type_string(), description = NULL, ...)
input_object(name, ..., description = NULL)