Filter recents view instances by package name

Filter instances of GroupTasks based on package name
as a part of support for multi-instance

Add a feature flag to toggle multi-instance features

See the video below for how to use the demo.
Note: some extra UI elements were added since video
was recorded, but the filtering process is the same.
http://recall/-/da585DRwKRZK3S2xxcQrSm/gW9HZnbCvGyH1DQiVizOW2

See go/multi-instance for more info about the feature

Bug: 253520408

Test: manually tested the instance filtering

Change-Id: I19c947ca353699096388b9fbbdca6d75cb0041a7