Exactly-one-of --function | --function-inline | --function-file | --function-python-inline | --function-python-file. Lives on its
own sub-struct + group so the required = true, multiple = false
enforcement is scoped to these five fields (clap derive’s
default-group rule would otherwise pull every outer field into
the same group). The group id is function_group rather than
function to avoid colliding with the bare --function flag’s
own arg name.
CLI-surface form for the --function* argument family: either a
fully resolved inline-or-remote spec (the JSON object form that
lands on --function-inline, or the docker-style remote-path
string on --function), the path to a JSON file (--function-file), or a Python harness
— inline (--function-python-inline) or file
(--function-python-file) — that produces the inline-or-remote
JSON at handler time.
CLI-surface form for the --profile* argument family — same
shape as FunctionSpec but wrapping the profile inline-or-remote
enum. See FunctionSpec for the variant semantics.