Sandbox (tryb dev):
Formularz wymaga Supabase Auth (GoTrue). W sandbox PostgREST-only użyj magic-link callback: GET /api/auth/callback?code=<JWT>&next=/dashboard. JWT secret: sandbox_placeholder_jwt_secret_must_match_supabase_in_prod. Role: sandbox-ceo=admin, sandbox-operator=operator, sandbox-viewer=viewer.