## What changed
- Define a versioned, length-prefixed JSON request/response protocol for the
machine-wide Windows sandbox provisioning service, including its named pipe
and network setup parameters.
- Add a readiness check that compares the recorded proxy ports and local-binding
policy with the requested provisioning settings.
- Share framed JSON I/O, sandbox-group creation, and SID resolution between the
existing elevated setup path and provisioning clients.
GitOrigin-RevId: d6250542d06f7646ffeb92150472e7d7fa1e5e66