Subfolder support for Dashboard List panel

[andrewmatthews]

Why is this needed:

Currently the Dashboard List panel allows you to select a folder to search for dashboard in. However, this will not search subfolders. This wasn't a big issue prior to Grafana 11 as you could only create a single level of folders. With the addition of subfolders in Grafana 11, this means that you can't find dashboards that are in a subfolder.

What would you like to be added:

The Dashboard List panel should search subfolders for matching dashboards. Potentially this could be achieved with a config option to maintain backwards compatibility.

Who is this feature for?

This feature would be for dashboard editors, who place dashboards in folders or who use the Dashboard List panel.