GoTrue Auth intermittent freeze: POST /auth/v1/token times out while /health responds OK (Next.js + Vercel, South America)

- [x] I confirm this is a bug with Supabase, not with my own application. - [x] I confirm I have searched the [Docs](https://docs.supabase.com), GitHub [Discussions](https://github.com/supabase/supabase/discussions), and [Discord](https://discord.supabase.com). ## Describe the bug Silent, intermittent freeze of GoTrue Auth: `POST /auth/v1/token?grant_type=password` times out (no response) while `GET /auth/v1/health` and REST/PostgREST respond normally. This freezes the login flow (client stays on a perpetual "Procesando…" state) and self-resolves after a while without any redeploy. It reproduces both in production (Vercel) and locally (`next start`), which points to connectivity/infra toward the Auth endpoint rather than app logic. Related: #46429 (same silent GoTrue freeze where POST endpoints die while /health returns OK), #43155 (POST /auth/v1/token timing out by region/ISP), #34386 (gateway timeouts on /auth/v1/token and /auth/v1/user). ## To Reproduce 1. `POST https://cyytdrhhclgqqutjjbtb.supabase.co/auth/v1/token?grant_type=password` with a valid apikey header and valid credentials → timeout, no response (fails 3/3 during the incident period). 2. `GET https://cyytdrhhclgqqutjjbtb.supabase.co` → 404 (normal) in ~363 ms. 3. `GET https://cyytdrhhclgqqutjjbtb.supabase.co/rest/v1/espacio?select=id` → 200 in ~973 ms (PostgREST/data layer fine). 4. Same `signInWithPassword()` call from the app (`src/app/auth/login/route.ts`, a Next.js Route Handler) → hangs; the serverless function blocks waiting on the sub-fetch to Supabase Auth. Measured from the owner's machine (general internet OK; e.g. google.com ~623 ms): | Request | Result | |---|---| | Base host `GET /` | 404 (normal) in ~363 ms | | `GET /rest/v1/espacio?select=id` (PostgREST / data layer) | ✅ 200 in ~973 ms | | `POST /auth/v1/token?grant_type=password` (Supabase Auth) | ❌ Timeout 3/3 (~12 s each) | | Same call from another route/region (agent burst) | ✅ 200 in 14/14 | ## Expected behavior Password sign-in …