new feat: instantiate a new VM without NIC

##### ISSUE TYPE

* Feature Idea

##### COMPONENT NAME

~~~
UI
~~~

##### SUMMARY

I need to instantiate a new instance from an existing template without a network card, or at least with it disabled since it contains services that connects automatically to the net at startup. AFAIK the "New instance" functionality does not allow to launch an instance without a network interface.

從 UI 的「New instance」流程開始，追蹤它如何根據現有 template 建立 instance 並設定網路介面。將完成定義為允許新的 instance 在沒有網路卡，或其網路介面已停用的情況下啟動，並透過相關的 UI 或 instance 建立測試驗證此行為。

由索引模型根據 Issue 內容生成。