Reload place list header and content separately

[flibbertigibbet]

Currently, whenever the place list or its header change, both are reloaded.

This used to be the case because the header would go away entirely to display error or no-results messages, and to display the loader icon. Now that there is a filter bar present that can return no results for a filter, messages need to be displayed below the header instead of removing it, so the filter can be changed again. Although the message content has been moved, the header still gets reloaded with the list.

When navigating between the home and map views, swap just the header content. There are already functions present to get the compiled HTML for both headers.

When reloading the destinations list, do not also redraw the header unless needed. Ensure the loader animation continues to display appropriately.