Guest Tools fail to load in macOS 27 beta

I’ve noticed that pasteboard sharing did not work after installing Guest Tools in macOS 27.

It’s because Guest Tools package carries over quarantine flag for .plist files. Clearing the flags and restarting the guest fixes the issue.

**PR** in vd_agent: https://github.com/utmapp/vd_agent/pull/4

**Manual fix**. Run in guest Terminal, then restart:

`sudo xattr -cr /Library/LaunchAgents/com.redhat.spice.vdagent.plist`
`sudo xattr -cr /Library/LaunchDaemons/com.redhat.spice.vdagentd.plist`

**Configuration**
* UTM Version: 5.0.4 (123)
* macOS Version: Host 26.6.1 (25G76) / Guest 26.6.1 (25G76)
* Mac Chip (Intel, M1, ...): M1

Start with the vd_agent PR linked in the issue and inspect Guest Tools packaging for quarantine flags on the two named plist files. Reproduce with the macOS 27 beta setup if available, then verify pasteboard sharing after Guest Tools installation and a guest restart.

Written by the indexing model from the issue text.