fix(examples-cli): support pull on Windows

Problem

vgpu examples pull fails on Windows before writing any files because safe destination resolution rejects win32 outright.

Expected and actual behavior

Expected: examples pull safely writes the example manifest and files to --out on Windows, matching macOS and Linux behavior.

Actual: the command exits non-zero with VGPU-EXAMPLES-FILESYSTEM and Safe destination storage is unsupported on win32.

Reproduction or use case

npx -y vgpu examples pull black-hole --out ./vgpu-blackhole

The prototype in this PR adds a portable Windows path while retaining destination, staging, lock-directory identity, and pathname-swap checks. It also exercises the complete examples suite in the Windows CI job.

Environment

• Windows 11
• PowerShell 5.1
• Node 22
• Reported with vgpu 0.3.1

Related work and proposal

Related: #383

The proposed implementation uses exclusive directory locks on Windows, retries transient EBUSY/EPERM sharing conflicts across publication, recovery, and cleanup operations, compares filesystem identities using bigint inode values, and leaves unknown platforms fail-closed.

Verification on the final branch:

• focused examples suite: 108 passed, 5 skipped
• pnpm run typecheck
• git diff --check

PR type

contribution