feat: Update Proxmox extension with various improvements and bug fixes

- Change listStates method to accept nullable integer for limit parameter.
- Modify TechnitiumDns class to return structured error messages on failure.
- Enhance VNC and xterm popup routes with user authorization checks.
- Update backups view to improve loading states and add unique keys for dynamic elements.
- Refactor cloud-init view to ensure proper data binding and improve user experience.
- Add wire:key attributes to various elements in views for better Livewire performance.
- Improve error handling and user feedback in the firewall view.
- Update server overview and statistics views to handle potential null values gracefully.
- Add new migration files to extend database schema with user-set icons and notes for Proxmox nodes.

extensions/Servers/Proxmox/views/server.blade.php

@@ -120,7 +120,7 @@
                 </div>
                 <div class="flex flex-col">
                     <span class="text-xs text-base/50">IPv6 Address</span>
-                    <span class="text-base">{{ $server->primaryIpv6->ip }}</span>
+                    <span class="text-base">{{ $server->primaryIpv6->ip ?? 'None' }}</span>
                 </div>
                 @if($status->status == 'running' && isset($status->uptime))
                 <div class="flex flex-col">