v1.8.19 — one answer per .env, on every platform

.env permissions are decided by vmware_policy.fsperms instead of POSIX mode
bits. On Windows a single command printed both a red "has permissions 0o666
(should be 600). Run: chmod 600" from this hot path — where chmod does nothing
— and a green "this platform does not express file permissions as POSIX mode
bits ... run: icacls" from doctor, about the same file in the same run. doctor
had been moved to the three-state check and the path that runs on every command
had not. An unmeasurable platform is now silent here rather than loudly wrong.

The vmware-monitor floor moves to 1.10.0: the investigation bundles this
skill re-exports had a cluster check that never matched on real hardware, and
the fix ships in Monitor.