feat(mfa): add MFA flow integration example in mfa_flow.html

[gyaneshgouraw-okta]

Summary

Add an interactive MFA APIs playground page that lets developers test the full Auth0 MFA flow — enrollment, challenge, and verification — directly from a single HTML file using auth0-react.

Changes

• Added a standalone MFA playground page that loads React and auth0-react via CDN/local bundle
• Config form collects Auth0 domain, client ID, audience, and scopes before initiating login — settings persist in localStorage
• On config submit, automatically redirects to Auth0 login (no intermediate "not logged in" state)
• After login, supports triggering MFA via silent token acquisition and displays MFA requirements
• Lists enrolled authenticators with the ability to initiate challenge and verify codes (OTP, OOB, recovery codes)
• Supports enrolling new authenticators: OTP (with QR code), SMS, email, and push notification
• Shows recovery codes section for backup verification
• Includes user profile display, logout, and flow reset controls

Testing

• Open static/mfa_flow.html in a browser (with auth0-react.js built alongside it)
• Enter valid Auth0 tenant domain and client ID — verify it redirects to Auth0 login immediately
• After login, click "Get token silently (Trigger MFA)" and verify the MFA flow works end-to-end
• Verify that refreshing the page shows the config form again (pre-populated with saved values)

In general, to avoid relying on ASI, terminate all JavaScript statements explicitly with semicolons, especially in codebases that otherwise consistently do so. This improves readability and avoids edge cases where line breaks change program behavior.

For this specific instance, the best fix is to add a terminating semicolon to the console.log statement inside the selectType function in static/mfa_flow.html. Only line 242 needs to change: turn console.log(">>>>>>details push", data) into console.log(">>>>>>details push", data);. No imports, additional methods, or other code changes are required, and this does not alter existing functionality.