fix: wpb-21356 offline-vm-setup script to manage VMs wiab-staging

[mohitrajain]

Removed command-line argument parsing - Script no longer supports --deploy-vm, --verbose, or -h flags; now only deploys the full 7-VM standard infrastructure.
Switched from static to dynamic DHCP IPs - VMs now acquire IPs automatically via DHCP instead of using pre-configured static IPs (192.168.122.10-33).
Replaced Autoinstall with Cloud-Init - Simplified provisioning from complex Ubuntu Installer to lightweight cloud-init with cloud-localds seed ISOs. VMs creation was taking 8 mins on physical hypervisor(KVM) enabled nodes and VM were in shut-off state once created, manual start was required. Now it takes 1.5 mins for 6 VMs.
Centralized SSH keys to deploy_dir/ssh/ - SSH keypairs now stored locally in the project directory instead of user's home .ssh/ folder with automatic permission validation.
Added .vm-env environment file export - Script now generates and exports all VM IPs as environment variables for downstream automation and inventory generation.
IP management was static - now it is DHCP based - better way to avoid collisions and in virtual network native way
If VMs are ready - old way was simple running check - modified to perform a ssh check

Change type

• Fix
• Feature
• Documentation
• Security / Upgrade

Basic information

• THIS CHANGE REQUIRES A DEPLOYMENT PACKAGE RELEASE
• THIS CHANGE REQUIRES A WIRE-DOCS RELEASE

Testing

• I ran/applied the changes myself, in a test environment.
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Tracking

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Motivation

Objective

Reason

Use case

[sonarqubecloud]

Quality Gate passed

Issues
11 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud