feat(auth): Add MFA with reCAPTCHA Enterprise and App Check example#912

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grushabshah wants to merge 3 commits intofirebase:masterfrom

grushabshah:recaptcha_enterprise_appcheck

Commits on Oct 8, 2025

auth: Prepare MFA auth with RecaptchaEnterprise and AppCheck into separate code
grushabshah
committed
auth: Update JavaScript SDK to add ReCAPTCHA Enterprise support
grushabshah
committed
auth: Implement RecaptchaEnterprise and AppCheck
grushabshah
committed