Standard JWT claims as defined by RFC 7519, extended with Supabase-specific fields.
This is the raw JWT payload — use UserClaims for a normalized, camelCase view.
Subject — the user's unique ID.
Issuer — typically your Supabase project URL.
Audience — who the token is intended for.
Expiration time (seconds since epoch).
Issued at (seconds since epoch).
Supabase role (e.g. `"authenticated"`, `"anon"`).
User's email address from Supabase Auth.
Application-level metadata set via Supabase Auth admin APIs.
User-editable metadata set via Supabase Auth.