feat: configure static WAN1 IP for primary and spare MX

Añade recurso meraki_device_management_interface para configurar
IP estática en el puerto WAN1 de ambos firewalls MX:
  - Primary: 213.229.159.145/28 (255.255.255.240), GW 213.229.159.147
  - Spare:   213.229.159.146/28 (255.255.255.240), GW 213.229.159.147

Los seriales del MX deben reemplazarse en wan.auto.tfvars.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

sites/BCN01-LAB/variables.tf

@@ -183,3 +183,16 @@ variable "appliance_ports" {
   default     = []
   description = "Configuración de puertos LAN del firewall MX."
 }
+
+variable "mx_wan_uplinks" {
+  type = list(object({
+    serial                  = string
+    interfaces_wan1_enabled = optional(bool, true)
+    wan1_static_ip          = optional(string, null)
+    wan1_static_subnet_mask = optional(string, null)
+    wan1_static_gateway_ip  = optional(string, null)
+    wan1_static_dns         = optional(list(string), null)
+  }))
+  default     = []
+  description = "Configuración WAN1 estática de los MX (primary y spare)."
+}