test(oidc): test auto_redirect_if_standalone_oidc and RP iniiate logout

tests/oidc/sso-only.env

@@ -0,0 +1,11 @@
+# Variables fed to Hurl for the SSO-only integration test.
+#
+# Ports distinct from test.env (8087 / 1080) so this can run alongside
+# `just api-test` or a concurrent OIDC suite without collision.
+base_url=http://localhost:8090
+oidc_issuer=http://localhost:1081
+oidc_authorize_endpoint=http://localhost:1081/auth
+# The OIDC client the fake IdP registers — same client_id whether the
+# SSO-only test or the plain OIDC test drives it. Used to assert the
+# `client_id=` param in the RP-initiated logout URL.
+oidc_client_id=oxicloud-test