Add custom image handling and access policy management

- Implement tests for custom KVM and LXC image creation, ensuring invalid sources and architecture mismatches are rejected.
- Introduce access policy management in CLI, allowing configuration of allowed sources and trusted proxies.
- Add NAT network configuration with validation for RFC1918 compliance and subnet parsing.
- Create panel access policy management, including normalization and evaluation of access decisions based on client IPs and forwarded headers.
- Develop middleware for enforcing access policies in the server, returning appropriate responses for allowed and denied requests.
- Enhance custom image downloading and validation, ensuring integrity and security of downloaded root filesystem archives.
- Include comprehensive tests for all new functionalities to ensure reliability and correctness.

.gitignore

@@ -72,3 +72,4 @@ backend/clicd
 api.md
 deploy-arm.ps1
 deploy-dhcp.ps1
+deploy-pve-windows.ps1