Add support for Opt-In Split Tunnel Overlapping IPs

[da-cf]

Description

Add two new fields to the device settings policy. This is to add API support for the Opt-In Split Tunnel Overlapping IPs feature:

1. lan_allow_minutes (uint) used to set the amount of time a user can access a LAN subnet.
2. lan_allow_subnet_size (uint) the allowed subnet size for the lan

Has your change been tested?

Added to existing device settings policy tests.

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)

Checklist:

• My code follows the code style of this project.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I have added tests to cover my changes.
• All new and existing tests passed.
• This change is using publicly documented in cloudflare/api-schemas
  and relies on stable APIs.

[github-actions]

changelog detected ✅

[github-actions]

This functionality has been released in v0.83.0.

For further feature requests or bug reports with this functionality, please create a new GitHub issue following the template. Thank you!