`renderClient` could only emit the authorization-code shape, so a
daemon client was expressed as an interactive one with an empty
redirect list. Authelia permits only the grants a client names, and an
omitted `grant_types` means authorization-code alone — so that shape
cannot obtain a token at all.
Measured against authelia 4.39.20, rendering exactly what this module
produced for `swarm-nats`:
client_secret_basic → unauthorized_client: The OAuth 2.0 Client is
not allowed to use authorization grant
'client_credentials'
introspection → {"active":false} (works)
Introspection is all the queue's responder needs today, which is why
nothing was visibly broken while the comment in `swarm-nats.nix`
described a grant that was never configured.
Adds `kind = "interactive" | "machine"` rather than inferring from an
empty `redirectUris`, because the two differ in what authelia permits
and not merely in what is populated. `openid` is dropped from a machine
client's scopes because authelia refuses that combination outright — a
daemon receives an access token and never an id-token.
An assertion rejects redirect URIs on a machine client: they are not
harmlessly unused, they mean the author believed a browser was
involved.
Refs #3274.
176d95c0f0