M21: add optional organisation identity

.env.example

@@ -14,6 +14,17 @@ TZ=Europe/Brussels
 # otherwise browsers will silently drop the cookie and no one can log in.
 SESSION_COOKIE_SECURE=false
 
+# Optional OpenID Connect login. Public demo role buttons remain available when enabled.
+OIDC_ENABLED=false
+OIDC_PROVIDER_NAME=Organisatieaccount
+OIDC_ISSUER_URL=
+OIDC_CLIENT_ID=
+OIDC_CLIENT_SECRET=
+OIDC_REDIRECT_URI=
+OIDC_ALLOWED_EMAIL_DOMAINS=
+OIDC_AUTO_PROVISION=true
+OIDC_DEFAULT_ROLE=rental_employee
+
 # Demo presentation (fictional org identity, badge/manifest, reset safety valve).
 # DEMO_ALLOW_RESET=false permanently disables POST /api/v1/demo/reset (403), independent
 # of role -- a safety valve for any environment where the dataset must not be rebuildable.