Update bubble bar swipe logic

After changes following swipe interactions are available for the bubble
bar:
1. stashed handle
- swipe up to show bubble bar, after swipe reaches unstash threshold, we
  show the bubble bar
- swipe down to stash bubble bar in the same gesture (without lifting
  finger), do this when swipe moves back below unstash threshold
- expand bubble bar on finger lifted when currently above unstash
  threshold

2. collapsed bubble bar (used in home or overview)
- swipe up and release over unstash threshold to expand bubble bar
- bubble bar can't be swiped down to stash it

3. expanded bubble bar
- no swipe interactions available

Bug: 371229061
Flag: com.android.wm.shell.enable_bubble_bar
Test: BubbleBarSwipeControllerTest
Test: manually test:
  - stashed bubble bar:
      - swipe up and back down => bubble bar shown and stashed
      - swipe up slightly and release => bubble bar not shown
      - swipe up and release => bubble bar shown, expands on release
  - collapsed bubble bar:
      - swipe down => no action
      - swipe up slightly => no action
      - swipe up and release => bar expands on release
Change-Id: I42aa59dc288446603e06a3d02419be38cf17fa1f