Fix Taskbar 3 Button y position on launcher home pause/resume

When app launcher pauses (not on app entry, but whilst home), we want to move the taskbar buttons to 3-button mode to avoid overlap with any popup UI (usually in the form of bottom sheets). To avoid overriding existing app entry animations, this is only implemented for cases of launcher pause without a launcher stop.

Flag: EXEMPT bugfix
Bug: 373977342
Bug: 374058222
Test: Manual
Change-Id: I727173b0ae7f3f8e23b1da6755ceda6493b311cb