## What changed
- Capture `CODEX_WINDOWS_REGISTERED_CORE=1` at startup and propagate the selected runtime to sandbox wrappers.
- Launch registered runners through service-recorded execution aliases, validating ownership, OS package identity, and the staged runner image before sending commands. Require service provisioning without falling back to copied helpers or `PATH` lookup.
- Preserve package context for sandboxed child processes and descendants so they can launch executables from the protected package directory.
- Refresh stale package registrations during readiness checks without blocking unrelated RPCs, and reconcile effective proxy settings through the service.
- Resolve setup ownership from the process token and avoid treating the server directory as a writable workspace when setup omits `cwd`.
- Record startup and command outcomes by runtime.
## Testing
Add coverage for runtime selection, package query validation, helper resolution, setup roots, proxy reconciliation, and command result reporting. Add an ignored integration test for environment forwarding, output, and exit status that requires an installed test MSIX and service provisioning in a Windows VM.
GitOrigin-RevId: 976d64039d611be4406c3d0e354820775f8eb6e4