feat: add vmctl bridge for vmwin

[AnrokX]

Adds a small vmctl bridge for the Windows VM behind the vmwin SSH alias.

What changed:

• info / status returns a VM health summary as JSON or a concise text report
• exec runs PowerShell on the VM through -EncodedCommand so quoting stays stable
• shell opens an interactive remote PowerShell session
• Added npm aliases plus short docs for day-to-day use

Validation:

• npx jest tests/unit/vmctl.test.js --runInBand
• node scripts/vm/vmctl.js info --json
• node scripts/vm/vmctl.js exec --command "Write-Output hello"
• node scripts/vm/vmctl.js shell
• npm run vm:info -- --json