Instead of having the "Current File" and then the individual libraries
containing indirect library overrides in the Library Overrides display
mode, only show what's in the current file. Agreement was that this
isn't very useful in this view, we may want to add it to the Hierarchy
view though (see T95802).
Part of T95802.
Also expands the top level ID type items ("Objects", "Materials", ...)
by default. See D14410 for details.
Reviewed by: Bastien Montagne
Differential Revision: https://developer.blender.org/D14410
1ff853a3f0