[flatstik]

Fixes #1982.

"Clear encryption keys from memory if a new device is inserted" can be disabled at any time without a restart: by unchecking it, by changing its registry value, or by stopping the VeraCrypt system service, which is what clears the keys.

This PR offers, when the option is enabled, to also prevent it from being disabled until Windows restarts. The prompt defaults to No, so nothing changes for users who answer No.

• The settings dialog asks the system service, through the existing elevated NotifyService path, to lock the option. The service locks it in the driver with a new admin-only IOCTL; the driver keeps that state until Windows restarts. A second IOCTL reports the state.
• While locked:
  • the service clears the keys on new device insertion, whatever the registry value says;
  • the service no longer rebuilds its list of known devices;
  • the service does not accept SERVICE_CONTROL_STOP;
  • the settings dialog shows the option checked and disabled.
• Setup already replaces a service that cannot be stopped when Windows restarts. When stopping it fails, Setup now also tells the running service that it has been superseded (a new control code). That service then does not reinstall its own, older boot loader or SetupConfig until the restart.
• The lock is requested after the other settings are saved. If the driver does not confirm it, an error is shown.
• The lock does not protect against an administrator, who can still terminate the service process. The prompt and the documentation say so.

The Linux and macOS counterpart is in #1984.

Testing:

• I do not have Windows, so this is not run-tested.
• It compiles with MSVC 2022 and WDK 10.0.26100 on a GitHub Windows runner. That covers the driver (including Ntdriver.c), Mount, Format, ExpandVolume, Setup and SetupDLL; no compiler warnings came from the changed files.
• An independent code review was done. Its findings are addressed: the superseded-service boot loader issue, the lock request no longer aborting the other settings, and the dialog when the service is not running while locked.

Since I cannot test on Windows (or macOS), please feel free to merge this, close it, or take it as a basis for your own implementation, as you see fit.