Support x-[app]:// style links to local documents on macOS (e.g., links to DEVONthink database)

macOS enables apps to register URL/URI schemes, such that clicking such a link will perform an action — for example, opening a particular file in a particular application. For example, in DEVONthink Pro 3, the user can copy an item in the database as a link, and then paste that link elsewhere. When the link is clicked, that item will be opened in the DEVONthink database.

As it stands, stand-alone links like x-devonthink-item://F8A89437-5017-4839-B1D1-959C82FC5974 are not clickable in Logseq. Logseq should support these schemes by making this type of link clickable. That way, users could refer to and access local files more easily.

(Explicit markdown-style links like [DT3](x-devonthink-item://F8A89437-5017-4839-B1D1-959C82FC5974) do work; but it would be nice if Logseq automatically detected stand-alone links.)