`docs/swarm/sso.md` already argues that the OIDC provider is derived from
the client list rather than carrying its own `enable` — authelia refuses to
start without clients, so a separate flag would be a second fact free to
disagree. The module header said it again, and the definition site said it a
third time.
The doc keeps the argument. The definition site keeps a short version,
because someone changing `oidcEnabled` needs the reason there and not two
files away, along with the part no doc carries: that it is unconditionally
true today and stays derived so the OIDC-gated code below is self-documenting
about why it is conditional.
The header also restated the users-store rationale the doc's "does not
provision users" bullet owns. What survives there is the one clause the doc
does not have — why a file backend is right rather than a placeholder for
LDAP, the subject set being bounded by one swarm.
503 comment lines to 495. Comment-only: still 36 module-eval properties.