Ensure drag indicators are cleared on transition abort

Overrides `onTransitionConsumed` in `WindowDragTransitionHandler` to
dispose of all multi-display drag indicators. This ensures that
indicator surfaces are properly cleaned up if a window drag transition
is aborted or consumed for any reason, preventing them from getting
stuck on screen.

Since the task ID is not available when this method is called, all
indicators are disposed of globally. This has a known, low-risk side
effect: if a user is dragging multiple windows simultaneously and one
transition aborts, indicators for all windows will be removed. This is
an acceptable trade-off given the rarity of the scenario.

Flag: com.android.window.flags.enable_window_drop_smooth_transition
Bug: 442613884
Test: manual test to ensure window drag working.
Test: atest WindowDragTransitionHandlerTest MultiDisplayDragMoveIndicatorControllerTest
Change-Id: I359797d156e3caff636e335add1a9d8c78af89ad