Thin Go layer over imgk/divert-go. Exposes Open/Close/Recv/Send and
maps the most relevant Windows errors to sentinels (ErrAccessDenied,
ErrDriverFailedPriorUnload, ErrInvalidHandle, ErrShutdown) so the
engine's recovery classifier can reason about them without importing
golang.org/x/sys/windows.
Verified imgk/divert-go@v0.1.0 API matches plan; only deviation is
Recv/Send returning uint (cast to int at our boundary).
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
