feat(pbs): post-install menu for Proxmox Backup Server

- Open the post-install menu from the PBS menu
- List only the customizable options that apply to PBS
- Offer the PBS no-subscription repository through the native repository API
- Upgrade PBS with the package list shown before applying it
- Remove and restore the subscription notice on the PBS web interface
- Install Figurine on PBS without the Proxmox VE aliases
- Offer the Helper-Scripts PBS post-install and microcode scripts
- Tune firewall bridges after the systemd udev rules in the automated post-install
- Add PBS repository policy tests and syntax checks
- Document the PBS differences on the post-install page
- Use backups in the Spanish PBS update message

scripts/post_install/uninstall-tools.sh

@@ -266,6 +266,12 @@ uninstall_subscription_banner() {
         fi
     fi
     
+    # Proxmox Backup Server ships the same widget toolkit without the PVE packages.
+    local -a ui_packages=(pve-manager proxmox-widget-toolkit libjs-extjs libpve-http-server-perl)
+    if [[ "$(dpkg-query -W -f='${Status}' proxmox-backup-server 2>/dev/null)" == "install ok installed" ]]; then
+        ui_packages=(proxmox-widget-toolkit libjs-extjs)
+    fi
+
     if [[ "$restored" == false ]]; then
         msg_info "$(translate "Performing complete package reinstallation...")"
         
@@ -274,7 +280,7 @@ uninstall_subscription_banner() {
         
         # Reinstall packages with force-confnew to restore original configs
         if apt-get --reinstall -o Dpkg::Options::="--force-confnew" install \
-            pve-manager proxmox-widget-toolkit libjs-extjs libpve-http-server-perl -y >/dev/null 2>&1; then
+            "${ui_packages[@]}" -y >/dev/null 2>&1; then
             msg_ok "$(translate "Reinstalled Proxmox packages successfully")"
             restored=true
         else
@@ -286,7 +292,7 @@ uninstall_subscription_banner() {
         
         # Second pass reinstallation to ensure everything is clean
         apt-get update >/dev/null 2>&1
-        apt-get --reinstall install proxmox-widget-toolkit pve-manager libjs-extjs libpve-http-server-perl -y >/dev/null 2>&1 || true
+        apt-get --reinstall install "${ui_packages[@]}" -y >/dev/null 2>&1 || true
     fi
     
     msg_info "$(translate "Cleaning cached files...")"