## Summary - Closes #80. - Password self-registration is on by default (`ENABLE_ACCOUNT_REGISTRATION`). `/user/create/` issues tokens and `needs_checkout`, and the web sign-up page already redirects into Stripe Checkout. - Browser SSO stays off (`ENABLE_SSO`, default false). Live Google and Microsoft client ids stay available for Drive linking, but public settings no longer advertise them, and login/signup OAuth start and callback are rejected. Stripe path checked before this change: Checkout builds a subscription session (Founders at $10/month, or `STRIPE_PRICE_ID`), stores a draft invoice, and signed `checkout.session.completed` / `invoice.paid` webhooks grant the plan. Checkout, webhook, portal, registration, and OAuth tests passed. ## Deploy note If `chat_backend_prod.env` or `chat_backend_beta.env` on the control node still sets `ENABLE_ACCOUNT_REGISTRATION=false`, that line overrides this default. Set it to `true` or remove it, and leave `ENABLE_SSO` unset or `false`. ## Test plan - [ ] `GET /api/public/settings/` returns `enable_account_registration: true` and `oauth.google` / `oauth.microsoft` false. - [ ] Sign-up form creates an account and redirects to Stripe Checkout. No Google or Microsoft button. - [ ] Checkout success grants the Founders plan after the webhook. - [ ] `/api/auth/oauth/google/start/?intent=signup` returns 403. Drive connect still starts. - [ ] Setting `ENABLE_ACCOUNT_REGISTRATION=false` closes `/user/create/` again. Reviewed-on: #81