enhancement: view agents from management server connected agents count

@DaanHoogland the problem is, API/UI will return say 4 agentscount but of these 4, 2 will be hypervisor host agents and 2 system VM agents. If I add a link for either the hosts view or the system VMs view, it can be confusing. Currently, we don't have a combined view for agents' list

_Originally posted by @shwstppr in https://github.com/apache/cloudstack/issues/12149#issuecomment-3588350206_

The original request for viewing connected hosts/agents from MS agents count was from @daviftorres in #12125

首先，透過 API/UI 追蹤管理伺服器的已連線代理程式數量，並比較 hypervisor 主機和系統 VM 的檢視畫面。釐清組合代理程式清單應如何表示 hypervisor 主機代理程式和系統 VM 代理程式，然後將完成定義為一種能夠明確檢視所有已連線代理程式的方式。

由索引模型根據 Issue 內容生成。