Add collapse/expand-all, window-shade/unshade

Summary:
BUG: 404344

FIXED-IN: 5.57

Add action icons for collapse-all and expand-all, as requested in D18358: Add buttons to collapse and expand all elements.

Test Plan:

24px icons not included in these previews because they're the same as the 22px icons with slightly wider margins

Reviewers: VDG, ngraham, trickyricky26

Reviewed By: VDG, ngraham

Subscribers: ndavis, ngraham, kde-frameworks-devel

Tags: Frameworks

Differential Revision: https://phabricator.kde.org/D19575