Enhances sign-up process with Turnstile integration for fraud
protection. Builds on top of fraud-protection-temp-emails.
Made with [Cursor](https://cursor.com)
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## Summary by CodeRabbit
* **New Features**
* Cloudflare Turnstile bot-protection across signup/sign-in flows
(including SDK JSON mode).
* Email deliverability checks via Emailable.
* Sign-up risk scoring with persisted risk metrics and country code
tracking.
* UI: country-code selector, risk-score editing in user details, users
list refresh button, and Turnstile signup demo pages.
* **Bug Fixes**
* Use actual sign-up timestamp for reporting/metrics.
* **Documentation**
* Expanded knowledge base on Turnstile, risk scoring, and env
configuration.
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Co-authored-by: Konstantin Wohlwend <n2d4xc@gmail.com>
Co-authored-by: BilalG1 <bg2002@gmail.com>
Co-authored-by: Armaan Jain <84474476+Developing-Gamer@users.noreply.github.com>
Co-authored-by: nams1570 <amanganapathy@gmail.com>
