Improve document on metadata fields required for status check

[newgene]

SmartAPI status check does requires servers and paths fields, in addition to the example values for the required parameter(s):

https://github.com/SmartAPI/smartAPI/blob/90f45105613d5d1d6cd6bf2181e4ba0b1e24647b/src/utils/monitor.py#L58-L64

Let's state these requirements cleanly in the faq item and update the wording in the status popup dialog.