Server Stats: millisecond timeout

### Description

Server Stats widget currently only supports s/m/h/d. When a server stats agent is not running, the page will hang until this timeout has elapsed. It would be useful to include a millisecond timeout so the page can still feel responsive when agents are offline.

Start by locating the Server Stats widget and its timeout configuration, then inspect how the existing s/m/h/d units are handled. Confirm the behavior when a server stats agent is offline and verify that millisecond values are accepted while the page remains responsive.

Written by the indexing model from the issue text.