feat: add support for creating clusters by matching package using resources

[Davidonium]

Add multi-AZ and GPU support to cluster package commands

Surfaces two fields from the booking API that were previously not exposed in the CLI.

cluster package list

• New GPU column showing the GPU resource value (e.g. 1000m), or n/a if the package has no GPU
• New MULTI-AZ column showing yes/no

cluster create

• New --gpu flag to select a package by GPU resource (same pattern as --cpu/--ram/--disk)
• New --multi-az flag to filter packages to multi-AZ only; acts as a narrowing filter alongside at least one resource flag
• Shell completion for --gpu, aware of other resource flags already set

cluster describe

• GPU resource allocation (base/reserved/available) is shown in the Resources section when present