Adds a Super Admin ("owner") identity — SUPER_ADMIN_EMAIL, else the
bootstrap/first user (super-admin.ts) — and closes the hole where a music
account could sign into the full platform:
- Rename EXPO_PUBLIC_CLIENT_ORIGIN -> OFFICER_APP_ORIGIN.
- PUBLIC_URL + OFFICER_APP_ORIGIN are owner-only origins; MUSIC_APP_ORIGIN
stays path-scoped to /api/auth + /api/music.
- Account backstop (origin-independent): a valid non-owner token may reach
only /api/auth + /api/music regardless of Origin — airtight even if the
header is omitted/forged.
- signin rejects a non-owner logging in from an owner-only origin.
Owner keeps full access (verified); music users are confined to the music app.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
