Enable password self-registration and keep SSO off.

Public sign-up was closed, and the live Google and Microsoft apps would have become sign-up buttons if the same flag turned both on.

.env.prod.example

@@ -59,9 +59,13 @@ EMAIL_USE_TLS=true
 # Captcha
 CAPTCHA_SECRET_KEY=replace-with-captcha-secret
 
-# Self-serve account registration (sign-up). Keep false until ready to open
-# public registration; set true in chat_backend_prod.env / chat_backend_beta.env.
-ENABLE_ACCOUNT_REGISTRATION=false
+# Password self-serve sign-up. Default true. Set false in
+# chat_backend_prod.env / chat_backend_beta.env to close public registration.
+# An explicit false in that secret overrides the code default.
+ENABLE_ACCOUNT_REGISTRATION=true
+# Browser SSO stays off. OAuth client ids below are for Drive linking until
+# this is set true.
+ENABLE_SSO=false
 
 # OAuth SSO — Google / Microsoft (#24). Never commit real secrets.
 # Register redirect URIs: