<!-- Add the related story/sub-task/bug number, like Resolves#123, or
remove if NA -->
**Related issue:** Resolves#34542
- Added SCEP endpoint for issuing certs for conditional access for Okta.
Functionally similar to host identity and Apple MDM SCEP endpoints.
- Changes file will be added later (this is a sub-task of the feature).
- A standard SCEP payload can be used to get a cert to an Apple device:
```
<!-- SCEP Configuration -->
<dict>
<key>PayloadContent</key>
<dict>
<key>URL</key>
<string>https://myfleet.example.com/api/fleet/conditional_access/scep</string>
<key>Challenge</key>
<string>ENROLLMENT_SECRET</string>
<key>Keysize</key>
<integer>2048</integer>
<key>Key Type</key>
<string>RSA</string>
<key>Key Usage</key>
<integer>5</integer>
<key>ExtendedKeyUsage</key>
<array>
<string>1.3.6.1.5.5.7.3.2</string>
</array>
<key>Subject</key>
<array>
<array>
<array>
<string>CN</string>
<string>Fleet conditional access for Okta</string>
</array>
</array>
</array>
<key>SubjectAltName</key>
<dict>
<key>uniformResourceIdentifier</key>
<array>
<string>urn:device:apple:uuid:%HardwareUUID%</string>
</array>
</dict>
<key>Retries</key>
<integer>3</integer>
<key>RetryDelay</key>
<integer>10</integer>
<!-- ACL for browser access -->
<key>AllowAllAppsAccess</key>
<true/>
<!-- Set true for Safari access. Set false if Safari support not needed. -->
<key>KeyIsExtractable</key>
<false/>
</dict>
<key>PayloadDescription</key>
<string>Configures SCEP for Fleet conditional access for Okta certificate</string>
<key>PayloadDisplayName</key>
<string>Fleet conditional access SCEP</string>
<key>PayloadIdentifier</key>
<string>com.fleetdm.conditional-access-scep</string>
<key>PayloadType</key>
<string>com.apple.security.scep</string>
<key>PayloadUUID</key>
<string>B2C3D4E5-F6A7-4B6C-9D8E-0F1A2B3C4D5E</string>
<key>PayloadVersion</key>
<integer>1</integer>
</dict>
```
# Checklist for submitter
## Testing
- [x] Added/updated automated tests
- [x] QA'd all new/changed functionality manually
## Database migrations
- [x] Ensured the correct collation is explicitly set for character
columns (`COLLATE utf8mb4_unicode_ci`).
<!-- This is an auto-generated comment: release notes by coderabbit.ai
-->
## Summary by CodeRabbit
## New Features
* Adds Conditional Access SCEP certificate enrollment support, enabling
hosts to obtain device identity certificates through secure certificate
enrollment protocol endpoints.
* Implements rate limiting for certificate enrollment requests to
prevent abuse.
## Tests
* Adds comprehensive integration tests for Conditional Access SCEP
functionality, including certificate operations, rate limiting
validation, and edge cases.
<!-- end of auto-generated comment: release notes by coderabbit.ai -->
Victor Lyuboslavsky
7c9c5b9a2e