feat: aft command for testing + stray test fixes

[haverchuck]

Description of changes: This PR provides a simple tool via aft to run integ and unit tests on any platform, with any connected device. It handles a workaround for a flutter tooling bug which prevents serial tests on desktop platforms, and aggregates the results from multiple test runs into a unified format.

There are still some failing tests, but at least now we can run on all platforms in a sane manner (minus web).

By submitting this pull request, I confirm that you can use, modify, copy, and redistribute this contribution, under the terms of your choice.

[codecov-commenter]

Codecov Report

Merging #1810 (6c91c81) into next (6373949) will not change coverage. The diff coverage is n/a.

@@           Coverage Diff           @@
##             next    #1810   +/-   ##
=======================================
  Coverage   42.91%   42.91%           
=======================================
  Files         115      115           
  Lines        7504     7504           
=======================================
  Hits         3220     3220           
  Misses       4284     4284           

Flag	Coverage Δ
android-unit-tests	∅ <ø> (∅)
flutter-unit-tests	25.09% <ø> (ø)
ios-unit-tests	89.08% <ø> (ø)

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