refactor: 25.04 is not an Ubuntu LTS release (#15)

* feat: 25.04 is not an Ubuntu LTS release

* doc: removed LTS from Ubuntu 25.04

builds/linux/ubuntu/25-04/variables-network.pkr.hcl

@@ -0,0 +1,36 @@
+/*
+    DESCRIPTION:
+    Ubuntu 25.04 LTS network variables used by the Packer Plugin for Proxmox (proxmox-iso).
+*/
+
+// VM Network Settings
+
+variable "vm_network_device" {
+  type        = string
+  description = "The network device of the VM."
+  default     = "ens18"
+}
+
+variable "vm_ip_address" {
+  type        = string
+  description = "The IP address of the VM (e.g. 172.16.100.192)."
+  default     = null
+}
+
+variable "vm_ip_netmask" {
+  type        = number
+  description = "The netmask of the VM (e.g. 24)."
+  default     = null
+}
+
+variable "vm_ip_gateway" {
+  type        = string
+  description = "The gateway of the VM (e.g. 172.16.100.1)."
+  default     = null
+}
+
+variable "vm_dns_list" {
+  type        = list(string)
+  description = "The nameservers of the VM."
+  default     = []
+}