- The frontend's `supabase.ts` falls back to a stub client (`http://localhost:54321`) that doesn't actually exist
- Backend tests mock auth entirely via `conftest.py` fixtures, so integration testing of the full auth flow is impossible
## Approach
Add a **GoTrue** container (Supabase's auth engine) to the local `docker-compose.yml`. GoTrue is a standalone Go service that provides the same auth API that Supabase cloud exposes. This gives us local email/password auth without needing Discord/Google OAuth providers configured.
**Architecture (Option 3):**
- **Local dev**: Own PostgreSQL + GoTrue container → full auth testing
- **Production**: Own PostgreSQL + Supabase cloud for auth (handles Discord/Google OAuth)
GoTrue will use the existing `db` PostgreSQL container, creating its own `auth` schema (separate from the app's tables managed by Alembic).
## Files to modify
-`docker-compose.yml` — add GoTrue service, configure env vars
-`.env.example` — add GoTrue-specific local defaults
-`frontend/src/lib/supabase.ts` — point to local GoTrue when in dev mode
-`backend/src/app/core/config.py` — may need local JWT secret default