CentOS (#16772)

* Add centos (ct)

* Update ct/centos.sh

* Clean up comments in centos.sh

Removed comments about the engine source and local core checkout.

* Uncomment var_arm64 assignment in centos.sh

---------

Co-authored-by: push-app-to-main[bot] <203845782+push-app-to-main[bot]@users.noreply.github.com>
Co-authored-by: Sam Heinz <sam@samheinz.com>
Co-authored-by: CanbiZ (MickLesk) <47820557+MickLesk@users.noreply.github.com>

install/centos-install.sh

@@ -0,0 +1,18 @@
+#!/usr/bin/env bash
+
+# Copyright (c) 2021-2026 community-scripts ORG
+# Author: MickLesk (CanbiZ)
+# License: MIT | https://github.com/community-scripts/ProxmoxVE/raw/main/LICENSE
+# Source: https://www.centos.org/centos-stream/
+
+source /dev/stdin <<<"$FUNCTIONS_FILE_PATH"
+color
+verb_ip6
+catch_errors
+setting_up_container
+network_check
+update_os
+
+motd_ssh
+customize
+cleanup_lxc