feat: support PBS hosts and remote PBS monitoring

scripts/utilities/pbs_update.sh

@@ -0,0 +1,38 @@
+#!/bin/bash
+# Use PBS's existing repositories; never run PVE repo, Ceph or major-upgrade scripts.
+BASE_DIR="/usr/local/share/proxmenux"
+LOCAL_SCRIPTS="$BASE_DIR/scripts"
+source "$BASE_DIR/utils.sh"
+source "$LOCAL_SCRIPTS/global/platform-functions.sh"
+load_language
+initialize_cache
+
+if ! pmx_is_pbs || [[ "$(pmx_platform_field supported)" != true ]]; then
+    msg_error "$(translate 'This operation supports PBS 3 on Debian 12 and PBS 4 on Debian 13.')"
+    exit 1
+fi
+[[ $EUID -eq 0 ]] || { msg_error "$(translate 'Run this operation as root.')"; exit 1; }
+dialog --backtitle "ProxMenux · PBS" --title "$(translate 'PBS package update')" \
+    --yesno "$(translate 'Refresh the configured APT repositories and review the PBS package upgrade? Repository files will be preserved.')" 10 80 || exit 0
+if ! apt-get -o APT::Update::Error-Mode=any update; then
+    msg_error "$(translate 'APT refresh failed. Check the PBS subscription and repositories in the native PBS interface; no source was changed.')"
+    read -r _
+    exit 1
+fi
+plan=$(mktemp)
+trap 'rm -f "$plan"' EXIT
+if ! apt-get -s full-upgrade > "$plan" 2>&1; then
+    dialog --textbox "$plan" 24 100
+    exit 1
+fi
+dialog --backtitle "ProxMenux · PBS" --title "$(translate 'Review package upgrade')" --textbox "$plan" 24 100
+dialog --defaultno --title "$(translate 'Apply PBS package upgrade')" \
+    --yesno "$(translate 'Apply the reviewed package upgrade now? Services may restart and packages listed for removal will be removed.')" 11 80 || exit 0
+if apt-get -y full-upgrade; then
+    msg_ok "$(translate 'PBS package upgrade completed. Check whether a reboot is required before your next backup window.')"
+else
+    msg_error "$(translate 'PBS package upgrade failed. Review the APT output before retrying.')"
+    read -r _
+    exit 1
+fi
+read -r _