feat(cloudflare): Add DNS, Firewall, and WAF services with checks

[HugoPBrito]

Context

This PR completes the Cloudflare provider by adding DNS, Firewall, and WAF services. This is part 4 of 4 PRs for complete Cloudflare support.

Depends on: #9425

Description

Adds 3 new services with 4 security checks:

DNS Service (1 check):

Check	Description
dns_records_proxied	Validates DNS records are proxied through Cloudflare

Firewall Service (2 checks):

Check	Description
firewall_has_blocking_rules	Ensures firewall has blocking rules configured
firewall_rate_limiting_configured	Validates rate limiting is configured at firewall level

WAF Service (1 check):

Check	Description
waf_owasp_enabled	Validates OWASP ruleset is enabled

Steps to review

1. Review DNS service in prowler/providers/cloudflare/services/dns/
2. Review Firewall service in prowler/providers/cloudflare/services/firewall/
3. Review WAF service in prowler/providers/cloudflare/services/waf/
4. Test locally:

   prowler cloudflare --api-token <token> --service dns
   

Checklist

• Are there new checks included in this PR? Yes (4 checks)
  • If so, do we need to update permissions for the provider? No
• [x] Review if the code is being covered by tests.
• [x] Review if code is being documented following this specification https://github.com/google/styleguide/blob/gh-pages/pyguide.md#38-comments-and-docstrings
• [ ] Review if backport is needed.
• [ ] Review if is needed to change the Readme.md
• [ ] Ensure new entries are added to CHANGELOG.md, if applicable.

License

By submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 license.