Refresh page content when changing the file associated with an application page ID

[gbl08ma]

When republishing a previously published page ID (by passing the previous ID to publishFile but using a different file name) the page needs to be reloaded on connected clients. This is to be more consistent with what happens when a page is unpublished (where the page turns into a 404/disappears in chat). The mechanism for conveying the change to the frontend can be similar (through an application event message used by the RPC return/event channel).

However, to consider: not selected sidebar tabs will retain their previous title. It may be wise to also trigger a sidebar tab register-unregister cycle to cause a configuration change to be broadcasted (similar to what is done when setSidebarTab is called with a different pageID). Keeping the same beforeTabID may be a challenge.