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## What this PR does
Add VPC support
### Release note
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```release-note
Added VPC support
```
<!-- This is an auto-generated comment: release notes by coderabbit.ai
-->
## Summary by CodeRabbit
* **New Features**
- Added Virtual Private Cloud (VPC) support with configurable subnets,
per-subnet network attachments, and generated subnet resources.
- Enabled subnet support for Virtual Machine and VM Instance: additional
interfaces, Multus networks, and conditional cloud-init/network secret
wiring for supported images.
* **Documentation**
- Added/updated docs and examples for VPC, Virtual Machine, and VM
Instance showing subnet parameters.
* **Chores**
- Expanded admin role permissions to manage Virtual Private Cloud
resources.
<!-- end of auto-generated comment: release notes by coderabbit.ai -->