decoupling task animation lifecycle from recents lifecycle

this will fix a few bugs but create acouple others. Luckily this is all behind a flag for now but will prevent us building on broken code

Test: Built locally and tested

Flag: com.android.launcher3.enable_fallback_overview_in_window

Bug:292269949

Change-Id: Ifd147d6f3dd3234dfb1afe369f83c241a205c6af