Update scripts to use Debian 13 and improve update logic

Bump default container OS version from Debian 12 to 13 across multiple LXC setup scripts. Refactor update_script functions for consistency, improve messaging, and standardize apt usage. Update Kimai install and update scripts to use setup_php, setup_composer, and fetch_and_deploy_gh_release helpers, and switch from MySQL to MariaDB. Update Kometa to use Python 3.13. Minor improvements to backup, cleanup, and service management steps in several scripts.

ct/kasm.sh

@@ -11,7 +11,7 @@ var_cpu="${var_cpu:-2}"
 var_ram="${var_ram:-8192}"
 var_disk="${var_disk:-30}"
 var_os="${var_os:-debian}"
-var_version="${var_version:-12}"
+var_version="${var_version:-13}"
 var_unprivileged="${var_unprivileged:-0}"
 var_fuse="${var_fuse:-yes}"
 var_tun="${var_tun:-yes}"
@@ -29,10 +29,10 @@ function update_script() {
     msg_error "No ${APP} Installation Found!"
     exit
   fi
-  msg_info "Updating $APP LXC"
-  $STD apt-get update
-  $STD apt-get -y upgrade
-  msg_ok "Updated $APP LXC"
+  msg_info "Updating LXC"
+  $STD apt update
+  $STD apt -y upgrade
+  msg_ok "Updated LXC"
   exit
 }