wire up
supabase

the board uses supabase for auth + realtime db. one-time setup, then we're live.

1. 01
   make a supabase project

   head to supabase.com/dashboard, click new project, region: us-east.
2. 02
   paste the schema

   in the project, open SQL editor → paste the contents of supabase/schema.sql → run.
3. 03
   copy your keys

   in project settings → API, grab the project URL and the anon public key.
4. 04
   add to .env.local

   append to .env.local at the project root:

   NEXT_PUBLIC_SUPABASE_URL=https://xxx.supabase.co
   NEXT_PUBLIC_SUPABASE_ANON_KEY=eyJhbG...
   NEXT_PUBLIC_SITE_URL=http://localhost:3000

5. 05
   set the redirect url

   in supabase auth → URL configuration, add http://localhost:3000/board/callback to redirect URLs. (and your prod url when you ship.)
6. 06
   restart the dev server

   npm run dev picks up the new env vars on next start. after that, pull up the board again.