WireGuard: give the Debian container 1 GB for WGDashboard (#18419)

WGDashboard builds its frontend with Vite during the install, and at 512 MB the kernel killed node: "Failed to compile frontend", then wg-dashboard would not start (11 runs in three days). The build finishes at 1 GB.

ct/wireguard.sh

@@ -22,7 +22,7 @@ if [[ "${var_os:-}" == "alpine" ]]; then
   var_disk="${var_disk:-1}"
   var_version="${var_version:-3.24}"
 else
-  var_ram="${var_ram:-512}"
+  var_ram="${var_ram:-1024}"
   var_disk="${var_disk:-4}"
   var_version="${var_version:-13}"
 fi