Tracker: Commands.h (and tracker_private.h) updates

* Add kDeleteSelection command alias in Commands.h, keep kDelete.
* Add kMoveSelectionToTrash and use it in place of kMoveToTrash.
  - kMoveToTrash in kept in tracker_private.h for use outside.
* Create a new constant kRestoreSelectionFromTrash for Tracker.
  - Move kRestoreFromTrash to tracker_private.h

Change-Id: I3cdefe97e8359fb53bacfc3319b046b051c6f7db
Reviewed-on: https://review.haiku-os.org/c/haiku/+/8225
Reviewed-by: waddlesplash <[email protected]>
Tested-by: Commit checker robot <[email protected]>
Haiku-Format: Haiku-format Bot <[email protected]>

headers/private/tracker/tracker_private.h

@@ -67,6 +67,8 @@ const uint32 kFSClipboardChanges = 'TCch';
 
 const uint32 kMoveToTrash = 'Ttrs';
 	// Used by ShowImage to delete images
+const uint32 kRestoreFromTrash = 'Tres';
+	// In case ShowImage ever wants to undo
 
 const uint32 kSelect = 'Tsel';
 	// Used by Open Target Folder tracker add-on to select files