remove whiptail from update scripts for unattended update support (#11712)

* Simplify Alpine update scripts to run upgrade

Remove interactive whiptail menus, loops and newt dependency checks from ct/alpine-docker.sh, ct/alpine-zigbee2mqtt.sh, and ct/alpine.sh. Each update_script now simply calls header_info, runs $STD apk -U upgrade, displays a success message and exits, simplifying and automating the update flow.

* feat(update-scripts): replace whiptail with msg_menu for unattended updates

Remove all whiptail dialogs from ct update_script() functions and replace
with msg_menu() - a lightweight read-based menu that supports:
- PHS_SILENT=1: auto-selects first (default) option for unattended mode
- Interactive: numbered menu with 10s timeout and default fallback

Converted scripts (whiptail menu → msg_menu):
- plex.sh, npmplus.sh, cronicle.sh, meilisearch.sh, node-red.sh
- homeassistant.sh, podman-homeassistant.sh
- vaultwarden.sh, alpine-vaultwarden.sh
- loki.sh, alpine-loki.sh
- alpine-grafana.sh, alpine-redis.sh, alpine-valkey.sh
- alpine-nextcloud.sh

Simplified scripts (removed unnecessary whiptail for single-action updates):
- alpine.sh, alpine-docker.sh, alpine-zigbee2mqtt.sh

Special handling:
- gitea-mirror.sh: replaced yesno/msgbox with read -rp confirmations,
  exit 75 in silent mode for major version upgrades requiring interaction
- vaultwarden.sh/alpine-vaultwarden.sh: passwordbox replaced with
  read -r -s -p, skipped in silent mode with warning
- nginxproxymanager.sh: exit 1 → exit 75 for disabled script

Infrastructure:
- Added msg_menu() helper to misc/build.func
- Added exit code 75 handling in update-apps.sh (skip, not fail)

Closes #11620

* refactor(update-scripts): remove menus where sequential updates suffice

- alpine-nextcloud: add apk upgrade as the update action (was missing)
- meilisearch: run meilisearch + UI updates sequentially (like bar-assistant)
- npmplus: run alpine upgrade + docker pull sequentially, no menu
- vaultwarden: update VaultWarden + Web-Vault sequentially, remove admin
  token option (interactive-only, not suitable for unattended updates)
- alpine-vaultwarden: just run apk upgrade, remove admin token menu

ct/plex.sh

@@ -29,10 +29,9 @@ function update_script() {
     msg_error "No ${APP} Installation Found!"
     exit
   fi
-  UPD=$(whiptail --backtitle "Proxmox VE Helper Scripts" --title "SUPPORT" --radiolist --cancel-button Exit-Script "Spacebar = Select \nplexupdate info >> https://github.com/mrworf/plexupdate" 10 59 2 \
-    "1" "Update LXC" ON \
-    "2" "Install plexupdate" OFF \
-    3>&1 1>&2 2>&3)
+  UPD=$(msg_menu "Plex Update Options" \
+    "1" "Update LXC" \
+    "2" "Install plexupdate")
   if [ "$UPD" == "1" ]; then
     msg_info "Updating ${APP} LXC"
     $STD apt update