[EW] Files side panel: refresh files list - automatically

When asking the agent to create a new page, it often doesn't show up in the listing unless the whole page is refreshed. The file list should automatically update when a new page gets created.

Source: https://jira.corp.adobe.com/browse/SITES-45629

Start with the Files side panel and the flow that creates a new page through the agent. Reproduce the missing listing update, then verify that a newly created page appears automatically without refreshing the whole page.

Written by the indexing model from the issue text.