Add Get-PveContainer, New-PveContainer, Remove-PveContainer,
Start/Stop/Restart-PveContainer, Copy-PveContainer,
Get-PveContainerConfig, and Set-PveContainerConfig. Mirrors VM
cmdlet patterns with LXC-appropriate parameters.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>