test(auth): manual test for email/password + MFA/TOTP flow

took demo app from PR and ingested it here as local test

- added ability to sign up a new email/pass, not just login
- added ability to detect unverified email, send verify email, and reload user
- added QR code display for TOTP enroll flow
- added native TOTP app open demonstration

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Co-Authored-By: James Bateman <[email protected]>

Author: mikehardy