Improve jank monitor debug overlay

Add status indicators for finished and cancelled CUIs. Also, add a delay
after the last CUI runs to ensure list of CUIs is legible.

Test: atest InteractionJankMonitorTest FrameTrackerTest
Flag: EXEMPT Debug-only change
Bug: 238923086
Change-Id: If5b730f50ce2215b51726092bc77e9c63aa523ef