Indicate target type in keyboard mode

[pokey]

The keyboard target has hidden state that the user needs to keep in their heads. For example, if you delete a target, you will end up with a zero-width keyboard target, but it is not an untyped target like you would get from switching into Cursorless keyboard mode. Thus, eg pouring that target will actually do nothing, because it won't auto-expand

Another example is setting target to an item in a list using "item" scope. In this case it's an item target, which eg inserts commas when cloned, but there is no visual indication of this fact. Ie if you instead selected the same item using a simple range, then it won't insert commas on clone, but you'll have no visual indication of that fact

We should have some visual indication of the type of the keyboard target