Alpha. Configuration for withClaims.
The composable middleware surface tracks @supabase/middleware 0.x — entry shapes, context keys, and config options may change between 0.x releases.
JWKS source used to verify tokens: an inline key set or a remote JWKS URL. Defaults to `SUPABASE_JWKS` (inline JSON) or `SUPABASE_JWKS_URL` (https endpoint) from the environment.